waterbear

I believe so but don't hold me to that.

Both of those are Jandy Aqualink part numbers. 520272 is the Pentair part number for the 10k-ohm thermistor, 20-feet cable temp sensor. Same part is used for both air and water so you need 2.

NO NO NO NO NO!!!! ALWAYS ALWAYS ALWAYS ADD ACID TO WATER. NOT THE OTHER WAY AROUND! If you ever had high school or college chemistry you learned this. Adding water to acid could cause it to splatter because of the heat generated. (This also applies to dry acid). Safety first! https://sciencenotes.org/add-acid-to-water-or-water-to-acid/ https://support.al.umces.edu/safely-diluting-acids-and-bases/ The referral to strong acids in these articles is not talking about the concentration but it is referring to the group of acids that completely dissociate (give up all their hydrogen) in water as opposed to weak acids that do not completely dissociate. There are 7 strong acids including sulfuric, nitric, and hydrochloric (aka Muriatic). All other acids are weak acids and include citric, acetic, oxalic, and hydrofluoric. Be aware that just because an acid is classified as weak does not mean it is not extremely caustic or dangerous.glacial acetic acid and hydorfluoric acid can cause severve burns and injuries.

Adding the chlorine is fine as long as the jets are running. I would still dilute the acid,whether dry or muriatic, before adding.

Are you designing the plumbing yourself or is a builder doing it? Flow rates are pretty much impossible to determine with the the information you supplies. However, you are considering a long run in a single pipe instead of 3 pipes and that will have an effect on the head pressure and flow rate, just as pipe length and diameter do Using one pipe instead of three will increase the resistance just as using a smaller diameter pipe would..

Phospates are a useless measurement. They are trying to sell you phosphate remover, which is not needed since phosphates are normally not the limiting factor in algae growth. As far as the other results go, how are they testing and did you get a computer printout? Pool store testing software is optimized to sell you as many products as possible. This is how they make money.

No surprise here. Pool store software is designed to see you as many chemicals at the can since this is how they make money. I worked in the retail end of the industry and tested more water than I care to think about. Some pool testing is better than others. If they are using strips they are either using a strip reader or just manually entering the readings. either way they are using strips. TDS is a bogus measurement and the fact that they don't test CYA is so they can sell you algaecide. Overstabilized water allows algae to grow unless you are running higher FC levels to compensate for the higer CYA levels.

the higher the TA the faster the pH will rise, particularly with a salt system because of the aeration created in the cell because of the generation of hydrogen bubbles so keeping the TA lower is important. Keeping the TA between 50-70 ppm will help because there will be less outgassing of CO2,which is the main cause of pH rise. Read these. It will help explain what's going on. https://www.poolspaforum.com/forum/index.php?/topic/52522-some-truths-about-ph-and-ta/ https://www.poolspaforum.com/forum/index.php?/topic/28846-lowering-total-alkalinity-howto/ The second one goes into the chemistry of TA and why high TA causes a faster pH rise Borate can be sued with a chlorine or bromine generator without problem and will help stabilize pH because it introduces a boric acid/borate buffer that, in conjunction with the carbonic acid/bicarbonate buffer we call TA helps "lock' the pH around 7.7 to 7.8. If you add borate do not lower the pH below 7.6 and don't lower it until it hits 8.0 or higher and keep the TA 50 to 70 ppm for best pH stability.

They buy Taylor reagents and equipment in bulk and repackage the so it's essentially a Taylor kit. If you look at the R-0003 reagent it is the Taylor reagent bottle! Like I said Taylor is the only company offering FSD-DPD testing. I don't count a repackaged Taylor kit as a separate manufacturer. To answer your question, yes this is the FAS-DPD titiration test with a color change from pink to colorless It is not" in one drop" as you stated. You count the drops and each one represents either .2 ppm when you use a 25 ml sample or .5 ppm when you use a 10 ml sample. IMHO, .5 ppm is more then enough precision for a pool or chlorine spa. If you are testing bromine then the 25 ml sample is better because if you are using this test yo would multiply .FC reading by 2.25 to get total bromine and if you are using the bromine specific test (only available from Taylor) then it will give you a precision of .5 ppm. .

For pool the suction valve for pool should be on and spa should be off the return valve for pool should be on and spa should be offl for spa the suction valve for spa should be on and pool should be off the return for spa should be on and pool should be off If your spa is a spillover spa that spills back into the pool you would have the spa return valve on and the pool suction valve on (all other valves off). this is your current setting according to your description of the valves but the picture shows that you have both pool and spa returns open and also the waterfall and the pressure side cleaner return. The pressure side cleaner line does not have a booster pump so it was probably for a Polaris 360 cleaner, which is the only one I know of that does not require a booster pump (there might be others on the market but I am not aware of any). Having the pressure side line open is fine. it just become another return. If you do get a cleaner then close the returns so only the cleanier line is open, have the waterfall and spa returns closed, and have the suction side set to pool. Waterfall should work when you have the pool returns running. The

@GeboYellow is (orthotolidine). It is only a test for total chlorine but it does not bleach out at high sanitizer levels. It is useful to see if there is chlorine in the tub. It will also test total bromine. It is usually found in cheap test kits and uses a comparator with yellow color blocks. It can be used to determine if chlorine levels are very high since it will turn dark yellow, orange, and then brown as sanitizer levels go up to about 100 ppm. Not a first choice for testing but can be useful as a backup test and it's better than strips. Red is DPD (diethyl-p-phenyleneldiamine). It uses a comparator with red color blocks. It can test both free chlorine and total chlorine. Combined chlorine can be determined by subtracting the free chlorine reading from the total chlorine reading. It will beach out at high sanitizer levels (bleachout can start at sanitizer levels of 5 to 10 ppm depending on the maker of the test) leading you to believe that your sanitizer is low or nonexistent when, in reality, it is high (which can also give you false high readings on pH tests). It can also test total bromine. It cannot test high sanitizer levels because of bleachout without diluting your sample with distilled water, which is a cumbersome process. It can give false high readings when MPS and ozone are used since they both test as chorine/bromine. Taylor does have a reagent pack that can remove the interference from MPS. Many men are unable to differentiate between close shades of red and find the DPD test difficult to read. Women are much better at differentiating close shades of red. DPD is the most common testing method used by most testing supply sellers (Taylor, LaMotte, Hach) and is also used in some strips. FAS-DPD (Ferrous ammonium sulfate/diethyl-p-phenyleneldiamine) is the gold standard for sanitizer testing. It is not a color matching test. It is a titration (drop counting test) that has a distinct color change from red to colorless that even color blind individuals can see and a precision as good as .2 ppm (for chlorine) or .5 ppm (for bromine). It can directly determine free chlorine and combined chlorine with no math and can also determine total bromine. It does not have the same bleachout problem (if it flashes pink and then turns cloear add more DPD power until there is a stable pink color) and can test much higher sanitizer levels (at least to about 20 ppm or even higher). AFAIK, only Taylor Technologies offer FAS-DPD test kits. FAS-DPD is used in their K2006 and K-2106 kits (which are the ones I recommend) and as stand alone kits. I would recommend FAS-DPD weekly and use OTO as a quick check to make sure sanitizer is present for daily testing or if you think sanitizer levels might be very high. before checking pH since you cant test pH when sanitizer is above 10 ppm (for Taylor pH reagents, some other brands of pH test become unreliable when sanitizer is above 5 ppm and some of the cheap ones 3 ppm, making them fairly worthless. @cranbiz Nope! Most Taylor kits use either DPD or FAS-DPD, only a handful of their kits use OTO. OTO is pretty much considered obsolete these days since it can only test total chlorine.

Yep. MPS is acidic.

As soon as you add the sodium bromide you will have a bromine spa and there will be no chlorine. Put in your bromine floater and start adjusting as per my pinned post. You might also want to read the other pinned posts in the hot tub chemistry section of the forum. They are all pinned for a reason! On next fill you will need to add more sodium bromide and follow the guide. As far as a floater, get a Pentair/Rainbow 335 (they come in both tan and blue) since they have great adjustability and make it easy to maintain the proper bromine level from the tabs. No, you are not and if you have everything balanced and running right then just shock before going on vacation and make any minor corrections when you get back. I've gone away for 3 weeks in July just shocking before I left (Im in Florida!) and when I came back my chlorine in both the pool and spa was 0 but the water was still clear, no algae, I just shocked and the rest of my water parameters were in line. Having 50 ppm borate does help. I would suggest just going on vacation and taking care of any problems when you get back. As far as daily maintenance, I hope you don't have any pets or kids because they cannot be ignored if you are too busy. Hot tubs and Pools are really no different. You can automate things to some extent but you MUST test the water weekly and make necessary adjustments and sanitizer should be checked a few times a week unless you are not using the tub. If you are not using the tub you still need to check weekly. Or you can ignore it and hope for the best. AS far as chlorine, once you have established your 20 - 30 ppm CYA you stop using dichlor and switch to bleach. Daily maintenance is normally adding a few tablespoons of bleach. That it. After a while you will know how much you need to add without testing and you will just have to do your weekly testing. For that matter CH and CYA only need to be tested monthly once everything is running smoothly. It sometimes is more work to get your bromine floater properly adjusted than it is to do the dichlor/bleach method. No, it's because you are not doing chlorine correctly. Be aware that children can overheat quickly in a spa because they have smaller body surface area than adults so the temperature should be set between 95 to 98 degrees and they should not be in for more than 15 minutes at a time! https://homeinspectioninsider.com/how-long-can-kids-stay-in-hot-tub/ https://hottubinsider.com/hot-tubs-safe-kids/ https://wellisspa.com/blog/can-kids-go-in-hot-tubs/ Finally, I assume you are using trichlor in your pool in a floater or feeder. The same things I said about overstabilzation and FC to CYA levels also apply. If you are running your CYA at the recommeded 30 to 50 ppm then a FC reading of 3 to 5 PPM is perfect but if your CYA is higher then you need to run your FC higher to achieve the same level of sanitation and algae control. IF you do this you will have no need for algaecides, phosphate removers, enzymes, and other pool chemicals that the pool stores love to $ell you! It's how they make money so having an overstabilized pool is in your best interest. You also do not need alkalinity increaser, it's just sodium bicarbonate AKA baking soda. Liquid pool chlorine is the same chemical as laundry bleach (sodium hypochlorite), just more concentrated. Borax is better at raising pH than washing soda (pH increaser, sodium carbonate) since it has minimal effect on TA while sodium carbonate will often raise the TA way too high, particularly with bromine, sodium hypochlorite, cal hypo, and dichlor. It is really only useful if you are running trichlor since trichlor is extremely acidic (pH under 3) which can cause both pH and TA to crash!

no Pretty much. IF you have persistent CC over 1 ppm then it might help but most people don't need it. You need a proper test kit. Get a Taylor k-2006 which can be used for both chlorine and bromine, It will test FC, CC, pH with acid and base demand tests, TA, CH, and CYA with a resolution that will allow you to properly balance your water. To use the K-2006 for bromine run the FC test and multiply the results by 2.25 to get total bromine. This way one kit can handle both your pool and if you decide to change the spa to bromine, also the spa. I gave you my advice. If you want to continue to use trichlor in your spa be my guest but I can offer no other help. Perhaps someone else can. "shock" level is dependent on your CYA level. Test strips DO NO have the precision required to determine this. You need a turbidity CYA test (disappearing dot test) such as the ones from Taylor (included in the K-2006 or available separately), Pentair/Rainbow, or LaMotte. Otherwise, you have no way of knowing if your FC levels are high enough to destroy VOC and oxidation byproducts. You want to add enough unstabilized chlorine (pool chlorine or bleach) to raise your FC to the desired shock level which could be anywhere from 10 ppm to 50 ppm or higher (if you have algae or biofilm). There is really no formula for chlorine demand. You need good test numbers. Period. Strips won't do it. OTO (liquid with yellow block comparator and some strips) won't do it and only tests total chlorine ( but it's useful to make sure you are not bleaching out a DPD test since OTO does not bleach out at high sanitizer levels) DPD is limited and suffers from bleachout (and is also used in some strips in addition to a drop based test with a red block comparator), syringaldazine (used in some strips) won't do it since it will give the same color at 10 ppm FC and 100 ppm FC so it's about as useful as DPD. FAS-DPD testing is a drop counting test with a color change from red to colorless that is easy even for colorblind people and does not involve color matching. It will directly test FC, CC, or total bromine and will give accurate and precise results with sanitizer levels well above 20 ppm. This is the test found in the Taylor K-2006 (chlorine) and K-2106 (bromine). As far as Bleach strength and dosing, you would need twice the amount of 6% bleach as you would for the 12.5% pool chlorine. WOW! Lots of excuses as to why you cannot care for your spa. Perhaps your wife is right. A spa is not hard to maintain but it does require some attention. As I said, I gave you my advice but it's your spa and you can do whatever you want with it but you obviously have some problems going on so perhaps you should rethink owning a spa.

They do not sell the K-2042 Monopersulfate Interference Remover. @Gebo Please check before making recommendations

Trichlor is way too acidic to use in a hot tub! HOt tubs have a very small water volume compared to a pool and it is very easy for chemical parameters to change quickly! Most spa manufacturers will void the warranty if you use trichlor. Also, trichlor adds 6 ppm CYA for every 10 ppm FC added while dichlor adds 9 ppm CYA for ever 10 ppm FC added. Overstabilization will happen quickly. A spa should not be over 30 ppm CYA! I have a suspicion about what these flakes might be. Exactly which Taylor kit do you have? Are you using strips to test CYA?. My guess is you are and you have a basic Taylor kit that does not test CYA, and probably uses DPD for chlorine testing, based on getting a FC of 5-10 ppm (which is not enough precision to be useful for anything!) Get a Taylor K-2006 and be done with it and stop using trichlor and only use dichlor unti your CYA reaches 30 ppm and no higher then switch to bleach. Keep your TA between 50 to 70 ppm and your pH between 7.6-7.8 and do not lower it until it goes above 7.8 for best pH stability. Shock when CC is 1 ppm or higher, don't use MPS. You can add 50 ppm borate for even better pH stability along with the other benefits of borate. I prefer using boric acid since it does not require pH adjustment like borax. I suspect the black flakes are from degredation of o rings or seals because of low pH from trichlor use. IF the skimmer is near an intake very low pH water could go directly into the plumbing while the pH in the tub reads much higher. Use 6% plain, unscented laundry bleach. both are sodium hypochlorite. Don't waste your money on phosphate removers. They only work if phosphates are the limiting factor in algae growth but nitrates also play a big part and are usually the limiting factor, There are no nitrate removers so there is nothing they can sell you! Maintaining your FC at the proper level for your current CYA level will keep the vast majority of pools and spas algae free. Phosphates are a non issue with proper maintenance. There is a relationship between CYA and FC. The higher the CYA the higher the FC need to maintain the SAME level of sanitation and algae control. The main problem is the use of stabilized chlorine (trchlor and dichlor). Both of these are net acidic (acidic on application and acidic on sanitation) so a much higher TA is needed to prevent pH from crashing to dangerously low levels. The small volume of water in a spa when compared to a pool means this changes can happen very fast and damage can occur before they are caught and corrected. Unstabilized chlorine (sodium hypochlorine/bleach, cal hypo) are net pH neutral (alkaline on application and acidic on sanitation) and require a much lower TA for pH stability since the main cause of pH rise is outgassing of CO2 and the amount of CO2 in the water is dictated by the TA. The higher the TA the higher the CO2.

OTO or DPD kit, they make both. (OTO has yellow color chips on the sanitizer side and DPD had red. DPD can bleach out and read low when it is really high. Get the Taylor. I have both (and had input into the design.beta tester when I was a Mod at TFP). Get the Taylor. FWIW, the TFP kit is pretty much a copy of the kit sold by Ben Powell of PoolForum before TFP existed. I also have that kit. They all use Taylor reagents. The TFP kit buys the reagents in bulk and repackages them. If your Poolmaster kit is OTO (yellow color block) you really don't need the included Taylor K-1000 OTO test kit included with the TFP kit. If you really want one I would buy it separately along with a K-2106 (for bromine) You can also get a K-2006 to test for bromine by doing the free chlorine test and multiplying the results by 2.25. Since k-2006 has a resolution of .2 ppm with a 25 ml sample it is going to give much more precision if you insist on running your bromine so low. The difference is the reagent (and the quality of the comparator). The Taylor reagent will not convert until you reach above 10 ppm sanitizer and can be used up to 20 ppm sanitizer if another reagent is added. The poolmaster kit is pretty useless for testing pH when the sanitizer is much above 5 ppm. The Taylor has a much better color block that is easier to read and also includes acid and base demand tests that can help you determine exactly how much acid is needed to lower TA safely. There is also a difference in the TA indicator. The Poolmaster has a color change from violet to yellow and it can be difficult to read. The Taylor changes from dark green to bright red and is very easy to read. FAS-DPD is a MUCH superior testing method and does not have the drawbacks of DPD (bleachout and close shades of red) or OTO (shades of yellow that are hard to differentiate at low sanitizer levels). Test with both and you will see there is no comparison between the kits. No, I don't work for Taylor! I just feel they make the best water testing kit for pool/spa use and it's worth every penny!If you think the price is too high think about how much you have invested in your tub. It puts things into persepcitive. Bromine should be run at 4-6 ppm. If the tub is properly maintained, no. In fact, when shocking you can re enter the tub once the bromine drops below 10 ppm. As far as skin irritation, bromine is a sensitizer (chlorine is not) so it is possible to become allergic to bromine. Non chlorine shock (MPS) is also a sensitizer and it is often used with bromine so I suspect that some of the cases of bromine sensitivity are really from the MPS used.

Ditch the N2 Ditch the MPS Maintain FC in the 6 ppm range and CYA at 30 ppm As far as the K-2042,not sure who you ordered it from but I just did a a quick web search and found it in stock from 2 different online resellers. You could contact Taylor to see if they are backordered on the kit. Also, contact the seller you got it from and see if they expect it any time soon or could send a refund if they don't expect it in soon.

shock it. Use bleach. make sure the sanitizer is around 12-15 ppm. wait for the sanitizer to drop below 10 ppm before entering the tub.

Invest in a Taylor Technologies K-2106 test kit. Strips are basically useless for several reasons, first and formoat that they do not have the precision required to properly balanced water. Computerized readouts do not mean a thing and they are designed to sell you products (I have previously worked in the retail end of the business and had been certified by LaMotte in their computerized testing system but also used Taylor liquid reagent testing which, IMHO, is far superior. and that does not leave enough of a reserve of active, fast acting sanitizer in the water. Silver is not fast acting and has no action against viruses. Every bather adds urine, feces, and sweat (chemical very similar to urine) to the water no matter how clean they think they are and can quickly deplete sanitizer reserves. This is why I am not a fan of 'mineral' (metal ion) systems. There is a pinned thread by me on the use of three step bromine that does touch on the chemistry, along with a pinned post by me on lowering TA which does explain the chemistry . Bromide ions from sodium bromide are converted into hypobromous acid (active bromine sanitizer) by an oxidizer. When the bromine sanitizer is depleted it reforms the bromide ions and the process repeat.Some of bromide ions can be converted into bromate, which does not convert back and forth, and deplete the bromide reserve. Ozone is the oxidizer most likely to do this. Sunlight has no effect on bromide ions but will deplete bromine sanitizer, which cannot be stabilized against UV like chlorine can by the use of cyuanuric acid. With a covered tub this is not an issue. Also, if you are using bromine tabs (which are mostly chlorine, btw) the dimethylhydantoin (DMHD)tends to 'stabilize' the bromine to make it more long lasting since sodium bromide can be eventually destroyed by repeated shocking with high levels of chlorine along with exposure to UV unless DMHD(which is how sodium bromide based algaecides work). Once DMHD is present it seems to help prevent the oxidation to bromate when compared to sodium bromide.

a few questions: What form of chlorine are you using? Dichlor, Bleach, cal hypo? What is your stabilizer (cyanuric acid) reading? How are you testing your water? Start by posting a full set of test results (FC, CC, pH, TA, CH, CYA) IF possible, post some pictures of the black flakes. White water mold. It's bacterial and usually occurs when sanitizer levels are low for an extended time. It usually occurs in spas running biguinide/peroxide (SoftSoak, BaquaSpa) but can happen in a chlorine or bromine tub. With chlorine it can also occur when the stabilizer level is very high, which can happen when DIchlor is the only chlorine source used. Purging and/or shocking with unstabilized chlorine (bleach or liquid chlorine) after getting stabilizer reading in line is the cure if you are running chlorine or bromine. Sometimes shocking is all that is needed Sounds like green algae, which often looks black. Pictures will help. Causes are chlorine too low or CYA (stabilizer) too high. What chlorine level are you maintaining? Chlorine level is dependent on the CYA (stabilizer) level. Never heard of this. Vinegar can be used to help remove mildew from hard surfaces when used full strength in a spray bottle but it is not as effective as chlorine,which is why most commercial mildew removers are chlorine. Never heard of it being used in a hot tub. and it does not play well with chlorine and can release harmful gases. Once again, post your water parameters and how you obtained them (dealer testing, strips, test kit with liquid reagents, test kit with a meter or strips used with a meter). IMHO, enzyme products are totally unnecessary and don't do much at all. They will not help with algae, mold, bacteria, etc. since they are not sanitizers. Their main use is to help remove surface scum from body oils, cosmetics, etc. but I have found that floating a lipophilic (oil loving) sponge such as a scumbug or scumball is more effective and costs a lot less.

How are you testing your Bromine? If you are using DPD or strips it is very possible that your sanitizer is actually high and your test is bleaching out? When sanitizer, either chlorine or bromine, is high it can cause the pH indicator to convert from phenol red to either chorophenol red or bromphenol red, which has the same color changes as phenol red except at a much lower pH range and if you are getting a reading of 8.3 and the indicator has converted all yo really know is that the pH is above 6.7. Your bromine reading of 1.2 indicated that you are either using some type of meter to test or you are using a Taylor FAS-DPD test kit with a 25 ML sample. If you are using the Taylor kit use a 10 ML sample which will give you a resolution of .5 ppm instead of the .2 ppm that the 25 ML sample gives. .5 ppm is all the resolution you need for testing sanitizer. IF you are using FAS-DPD then your pH is high and you should lower it. Procedure is at end of post. If your TA is low you would use baking soda to raise it since it will raise TA with a minimal effect on pH. NEVER use washing soda unless you need to raise pH and TA. Washing soda is usually only necessary for swimming pools using trichlor, which is very acidic. A TA of 45 is not out of line for a tub, where the recommended range is 50-70 for best pH stability., Read this: https://www.poolspaforum.com/forum/index.php?/topic/52522-some-truths-about-ph-and-ta/ If you do want to raise the TA I would not go higher than about 70 ppm. Here is what to do: 1. Assuming your are using FAS-DPD testing for sanitizer first use an acid demand test to determine how much acid is needed to lower pH to desired level. I would suggest 7.6 to 7.7 if you are using borate. 2. Once pH is at target test TA and determine how much is needed to raise TA to target value. Test 24 to 48 houirs later and then test pH again. 3. lower pH to desired level using the acid demand test once again since baking soda (sodium bicarbonate) will cause a slight pH rise. If you lower the pH a bit lower than your target don't worry, it will rise on it's own. Final ardvise, ditch the Frog and raise your bromine to 4-6 ppm. since you are already using 3 step bromine. Feels balanced? Not sure what you mean. A tub is balanced when all the chemical parameters are where they are supposed to be. It does not have any effect on the 'feel' of the water unless the pH is way out of line or the CH is extremely high.

It is a rebranded Nature 2 mineral stick. It contains silver nitrate and does require the use of chlorine for shocking and MPS (in conjunction with the silver and the hot water) as a sanitizer. I am not a fan of silver "mineral stick" systems. It's not really any different that the Frog systems. Is your water al cloudy green or a clear green? Cloudy indicates algae and is because you do not have a residual sanitizer in the water. Did you shock with chlorine (dichlor is the usual choice but I prefer bleach) to activate the system and have you been adding the MPS after every soak? Have you been shocking with chlorine weekly? Is your water a clear green color (and does your tub have a blue acrylic shell? If you you have iron in your water. Iron will color the water yellow and when viewed against the blue color of most tubs it makes the water look green. Both of these are water balance issues and once we determine which is your problem we can take it form there.

It is a calcium buildup which can be either calcium carbonate (easy to remove) and calcium silicate (difficult to remove) There are several ways to do this. For calcium carbonate you can use a commercial pool tile cleaner with a scrub brush Muriatic acid (use proper safety gear and respirator) is the easiest and fastest , citric acid solution (will deplete chlorine until but will also help with rust and some other metal staining), pool tile soap (either by itself or mixed with muriatic acid) with a scrub brush or pool tile brush, spray on a mixture of equal parts white vinegar and water and scrub with a brush (requires a lot of scrubbing). Do not use any abrasive tools (pumice stone, Magic Eraser) because they can damage the gelcoat on your fiberglass pool since you indicated that the 'tile' is actually part of the fiberglass and not actual tile. If it is calcium silicate it is next to impossible to remove without using an abrasive, which you cannot do on a fiberglass surface.. If you had an actual tile line with real tile this would not be a problem. My favorite is tile soap and muriatic acid or a commercial tile cleaner with a tile brush.

MPS is a known sensitizer and many people get skin reactions from its use.