RMS
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Posts posted by RMS
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My pool maintenance guy is repeatedly slow in adding more salt after the "low salt" warning light shows on our control panel (sometimes as long as two weeks before he gets to it). My salt cell has now failed. I am curious if anyone knows if having low salt content in the pool (because my pool guy is lazy) could have caused the cell to fail.
We have an Aquarite Goldline T-CELL-15 Turbo Cell.
Any insights on this are much appreciated.
Thank you.
The Y has a salt cell, Chloromatic for both hot tub and pool, of which I'm the pool operator. From my understanding the cell can burn up if you have either too high or too low salt. Too much salt will cause the fins inside the cell to crust over and that will affect performance. Too little and they will jsut be burning water, and the fins will burn up themselves.
http://www.clean-pool-and-spa.com/salt-wat...ming-pools.html
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I was addressing the strictly chemistry side of the statement. You threw in a lot of other variables and were looking at it from another side..
The important thing is we never heard back from the guy, he never answered the questions, esp how can you save $7,000 by throwing in bicarb?
Well, here I am and I will answer your question on how I helped the Y save so much money.
Before me:
The guards (mostly 16-17 yr old kids) were using 35 gallons of acid per month at $35.99 per case of 4 gallons. $323 per month times 12 months is $3886 per year. Calcium per year $479, Bicarb $180, Salt $957 and Phosfree $1583 (at $32.99 per bottle/4 per month)
Total=$7085 per year
Acid to drop the pH to 7.0, then 25lbs to bring it up to 7.4. After 2 days the pH is 7.6, then 2 more gallons of acid, now it's below 7.0, so 50lbs. of bicarb, etc...throughout the entire month. There were days when they would put in 2 gallons of acid at 8:30pm, then add 50lbs. of bicarb at 9pm.
Salt (50lb. bags) and sometimes the salinity in the water was 3700 - 3900. Burned out a Chloromatic cell ($4500) and went through 3 of them in 2 years.
After me:
Acid $73 (this includes both the pool and hot tub)
Calcium $25.99 (1 bag per year)
Bicarb $60 (pool and hot tub)
Salt $545
Phosfree $0 (don't need it)
Total=$703 per year
Difference=$6342
This past June our chemical order was $65 for the entire month.
Not to mention we haven't had to purchase another Cloromatic cell because it is properly cleaned each month.
So I didn't save the Y money by "throwing in bicarb." I did it using common sense, proper training, and an understanding of what the pool needed, how it needed it, and when it needed it. I kept it simple.
The members are happy, the pool is happy, and so is the management. And it's all documented. Nuff said.
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Hey all,
First off I work at a pool club and a had today we had a chemical explosion. Thankfully I was not in the pumphouse but one of my friends was in there. I got a call when this happened and went to work, unfortunately the club was blocked off. I talked to an officer and they said it was an explosion caused by an oxidizer. I assume this can be chlorine tablets?
Does anyone know the cause of this? The pump house has little to no circulation which I was wondering if it was a factor. Also what are the health risks included with this? Last I heard was that my friend could not see and was rushed to the hospital. Any information on this topic would be great, thanks for your time.
Mike
Many times you may have an explosion when you add water to a chemical, instead of the chemical to the water, or if you mix wet and dry chemicals like muriatic acid to Calcium Hypochloride, which is granular chlorine.
Always keep liquid and dry chemicals seperated and wear goggles and rubber gloves when dealing with chemicals.
http://www.clean-pool-and-spa.com/swimming-safety.html
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I have a 17K gal plaster/gunnite pool in SoCal.Currently in process of draining and will begin refill overnight. Draining 75% bcause calcium hardness 630, tap water is 240 (confirmed with city of Anaheim).Just received new Taylor 2006 test kit, have all chemicals. NOW WHAT ??? I imagine certain chemicals should be added while filling or right after it is filled in anticipation that they will be needed. My question is which ones and how much? I cant be testing for everything every 5 minutes or I will run out of chemicals in test kit.
I guess I need some kind of start up routine. I have been maintaining my pool myself for 25 yrs with no serious problems, but I think I have just been lucky. I have been visiting this forum almost daily for last 6 mo and was never aware of the complexity of the water chemistry, it wasnt that way when I started.I want to do it right this time
HELP-Joe
Water is complex, but you don't need to make it that way. Just remember the basics and you'll be fine:
chlorine 1.5-3.5ppm
pH 7.6-7.8, not 7.2. You'll use too much acid
Alkalinity 80-100
Hardness 150-250.
Cyanuric acid 50-70
Being in CA you probably won't need to add calcium to your pool, so 240-250 is fine. You did good in testing your fill water because you need to do this in order to have a starting point.
Chlorine...use about 1lb. of Calcium Hypochloride. This will bring it up to around 4ppm.
pH...depends on the pH of your water, but I wouldn't add any Sodium Bicarb. unless the pH is below 7.2. You'll need Sod. Bi
Alk. Increase with Sod. Bi....http://www.clean-pool-and-spa.com/pool-alkalinity.html will tell you how to raise it. The pH section will tell you how to raise the pH without much to the TA.
Muriatic Acid, gloves and goggles for safety
Chlorine tablets
http://www.clean-pool-and-spa.com can handle your questions
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Over the past few months I have noticed that the frequently my salt system is not generating any chlorine and that the salt level is indicating below 2400, instant salinity is normally around 29000 - 30000 and this concentration is supported when I've had the water checked at the local pool store. I've cleaned the cell until I'm sick of it and there's never been any substantial build up on the plates. Keeping the yellow-green algae down is a daily task and I have taken to adding some liquid chlorine from time to time. The local pool store has given me a couple of easy practical suggestions for checking if the cell is producing Chlorine and it is.
Anyway, if I switch the power of the Aqua Rite control box off and then back on again and wait a few seconds the salinity indication will start to rise (Not always but more often than not) and the chlorine generation will continue to work as long as I stand there and watch it. Inevitably when I go away and come back I have a bunch of flashing lights and depending on the indicated salt level it may or may not be generating chlorine.
The salt system is currently in it's 4th summer (Southern California) and the water temperature is currently 85 - 87 during the day and around 80 at night. I am not the most ardent pool chemistry monitor and during the winter it might go many weeks between checks. I am always having to add Muriatic Acid and have also had to spend several dollars on the Conditioner to bring it up from 50 to 90(ish). This is the second cell I've installed in the system. The first did great for the initial season and then I struggled through most of the second summer trying to get it to work (very similar symptom to my current problem) until I relinquished and bought another cell. Immediate satisfaction and a relatively trouble free summer last year but now I'm back to the same old story and it looks like these cells will only last about one summer.
I run the pool pump using the following equation, temp in C divided by 2 equals the number of hours to run the pump. So the pump runs a couple of hours a day even in the winter up to 12/13 hours/day currently.
So the cell makes chlorine until it thinks the salt level is too low and then shuts down. What is making it think the salt level is low? I could provide the diagnostic readings but they do vary although appear to be within limits most of the time.
Pool operator for the YMCA
We have a salt system, Chloramitc for both the hot tub and pool. When our system was not producing chlorine, we cleaned the cell, but you've done that already. We also tested the salinity with a Myron Salinity Meter. We got a bottle of their salt water and calibrated the meter to 3000. This did the trick. The meter was off.
You can call TMI Salt Pure based in Washington state. I also weekly calibrate the Chloramatic box with the test from the salinity meter and calibrate the salinity meter once per month with the salt solution I get from TMI.
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Has anyone else had problems with chloramines in their make up pool water? I maintain a 34,500 gal. pool that uses bromine and ozone as the sanitizers.We also use a cat controller for pH and ORP but when I add fresh water my orp drops about a hundred points per 1000 gal. If anyone else as had this problem I would welcome any suggestions.
Chloramines are a chemical combination of chlorine and ammonia. It can be really irritating, especially for a pool operator. I'm lucky because here in Oregon, we have pretty good water, as far as tap water goes, Chlorine is 0, Alk. 30, pH 8.0, hardness 30.
The only way I know to get rid of chloramines is to blast them with chlorine or another kind of sanitizer. http://www.clean-pool-and-spa.com/swimming...l-chlorine.html
Have people take showers and use the bathroom before entering the pool. Also, if it's an indoor public pool, be sure you have good ventilation and a good source of fresh air. Never ever turn the exhaust off. If you close the pool at night you may want to put a couple of high powered fans on the deck at the opposite end of the exhaust, blowing towards it. This moves the chloramines across the water to the exhaust.
We started this a few months ago and it has reduced the chloramine level a bit. It's better than shocking and adding tons more chemicals to the water.
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If you look at the derivation of the saturation index at the bottom of my spreadsheet here you will see that there is NOTHING in the derivation specific to public water systems, to pools, or to any other aspect of the environment. It is simply and ONLY a formula based on chemical equilibrium saturation with calcium carbonate. It is not a rate equation, so will not tell you how quickly any dissolving of plaster or formation of scale will take, but it does tell you if it is possible in either direction (because it is based on thermodynamics) -- when the index is near zero there can be no dissolving nor scaling. When the index is negative, then dissolving of calcium carbonate is possible, but may take a long time; when the index is positive, then scaling can occur, but it can take a long time.
So use of the index is very reasonable, but the Langelier index used by the pool industry isn't up to date with the latest equilibrium constants and temperature dependency. My spreadsheet is closer to current info and pretty much matches the Taylor watergram (though the watergram doesn't have TDS as a variable which affects ionic strength).
The only real controversy for the index is with regard to metal corrosion (as opposed to dissolving calcium carbonate in plaster). Some believe that saturating the water with calcium carbonate forms a thin film on metals to inhibit corrosion while others think that isn't particularly important and other factors (especially pH) are more important. See this link, for example.
Richard
Thanks for the info chem geek. You have really researched this topic and for that I thank you. This is what I know:
I have an 80,000 gallon pool with the alkalinity of 70 and the pH of 7.6. I want to get the alkalinity to 100. I add about 570oz. of Sodium Bicarb. with the method above and allow it to sit for 2-3 hours. Come back, fire up the pump for 5 hours, (full turn-over) and re-take the alkalinity test. The alkalinity is 100 and the pH is still 7.6 and it will stay there for 3 months. All this with 2000-3000 people per week swimming in the pool. Maybe add 1 gallon of acid every 25 days or so to keep the pH in check.
Doing this, among other things, has saved the YMCA nearly $7000 in chemicals since July 08. They couldn't be happier and the members couldn't be happier because now they now have a well balanced pool that uses 80% less chemicals than in previous years. And it's all documented.
Best regards
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So I have been helping a friend with his pool that had a huge failure of sanitation....he was using peroxide and once the summer heat and sun combined with fertilizers being blow in from the surrounding fields he had a massive alge bloom when he got back from stugis.
Since draining was not an option....he didnt want to use 14,000 gallons of water, and the peroxide was all used up anyways....we started the switch to chlorine as he has a pool party for his kids next Saturday.
We started by bring his CYA up to 40ppm....then brought the FC to 20ppm and have held it there since Monday. Scrubbed the whole damn pool every day twice a day...and things are getting nice. It is cloudy white, which is what I assume just particulate matter from the death of all the organics. His FC is begining to stabilize to about 25% demand overnight. So we are now in the process of getting his PH and TA under control.
His TA is at about 410........what is a good level to keep it at in an outdoor, uncovered, vinyl lined, Minnesota pool?
We have the Borates at about 25ppm (I know, too low, but he will be shutting down the pool in a month so does not want to spend the money for more, hey...it's not my pool), the chlorine will be stabilized at about 4ppm, with CYA at 40PPM.
thanks for the help!
With pretty much any pool you'll want these readings:
Chlorine 1.5-3.5ppm
pH 7.6-7.8, not 7.2. You'll use too much acid. You may hear to keep your pH at 7.2, which is using the Langelier Index. This was initially used for public water systems, not for pools.
Alkalinity 80-100ppm
Calcium Hardness 150-250, not up to 300-400.
Go to:
http://www.clean-pool-and-spa.com/swimming...nance-tips.html
http://www.clean-pool-and-spa.com
for more info on how to accomplish this.
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I bought a new Caldera Geneva about a month ago and am suddenly having problems maintaining consistent chemical levels.
It has the inline cartridge system that holds a bromine & mineral cartridge.
My alkalinity & PH levels starting dropping and I can't get them to back to normal.
I've tried shocking & several tablespoons of spa-up and haven't noticed much of a difference.
I also replaced both the bromine and the mineral cartridge and it didn't help.
Also, the bromine level is running a little high - I assume I can just lower the number setting on the bromine cartridge?
Any advice appreciated!
Thanks
Balancing your chemicals is fairly easy, but there are some techniques to employ. If you're throwing chemicals at a problems, the problem will always get worse, not better.
Too much info to go over here, but you can go to:
http://www.clean-pool-and-spa.com
for pretty much all you need for chlorine, pH, alkalinity, and hardness. For your Hot Tub use bromine because it seems to be a bit better at higher temps. than chlorine.
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I wanted to ask and answer this question because there is so much misinformation about using bleach in swimming pools.
Much of the misinformation is spread by pool stores so that they can sell you their overpriced chlorine. Most of pool store chlorine contains additional chemicals, such as calcium and cyanuric acid, that will build up and cause you trouble.
______________________________________________________________
Answer:
Yes, you can. In fact, it is one of the best sources of chlorine for your pool
I have thoroughly researched this, and I use it all of the time. I have contacted Clorox and the company that makes 80% of all liquid chlorine and private label bleach in the country. They have told me that regular bleach is the exact same thing as liquid chlorine, just at a lower strength.
You can call the 800-292-2200 number listed on every bottle of Clorox to hear the recording of how to use Clorox in your pool.
From http://cloroxprofessional.com/pdf/servicebulletin.pdf
"This product is a 6.15% sodium hypochlorite solution, containing approximately 5.84% available chlorine by weight. The purity of its ingredients and the carefully supervised process of its manufacture make this product a quality source of chlorine for water treatment in swimming and wading pools. This product is especially suitable for use in chlorinators as it is a liquid and has no insoluble particles. This product is widely used as a
source of chlorine for swimming pool sanitation and does not have any adverse effects on materials used in pool construction including swimming pool liners."
This is the Clorox bleach that is sold at the big hardware stores, like Lowe's or Home Depot. It is the same bleach as regular Clorox. It is just labeled differently.
Pool stores love to mislead people with a bunch of misinformation so that you will be dependant on them for their expensive chemicals. Most of what they sell is completely unnecessary. Algaecides, phosphate removers and such are nothing more than high mark-up profit makers.
The pool store will tell you that bleach is not strong enough to do anything. Complete nonsense. Bleach is just as strong as any other source of chlorine. The concentration is lower, so you have to add more total weight of bleach, but this is just water and a tiny bit of salt.
Bleach is the cleanest and easiest way to chlorinate your pool with the least amount of adverse effects. Pool store chlorine such as Calcium Hypochlorite, Lithium Hypochlorite, Dichlor etc are all inferior to bleach in virtually every way.
Pool stores will tell you that bleach is not stabilized, and will burn off way too fast. More nonsense. Outdoor pools should already contain about 40 ppm of Cyanuric Acid (Chlorine Stabilizer). When the bleach is added, it rapidly combines with the cyanuric acid to become stabilized.
Some pool store employees will claim that bleach contains ammonia, detergents or other such chemicals. There are no such problem chemicals in bleach. The only thing you need to be careful about is to get regular, unscented 6% Sodium hypochlorite bleach. Be careful not to get a scented or otherwise "special use" bleach.
Many pool store employees have no real experience taking care of pools and don't really know what they are doing. They are just following a script written by corporate HQ and the big chemical makers that is designed to make the largest profit possible.
One of the best things a person can do is to get their own good test kit such as the Taylor 2006 Complete (FAS-DPD Chlorine) and test their own water. http://www.taylortechnologies.com/products...&KitID=2230
You can use bleach, but you should use it only for emergencies. As was stated, bleach is about 15% chlorine, while Calcium Hypochlorite is about 65% chlorine. Why would you use 12% when you can get 65%?
Use Cal Hypo. and get more bag for your buck. The only drawback is when you shock you'll have a layer of calcium of the bottom of the pool that will need to be vacuumed.
http://www.clean-pool-and-spa.com/swimming...l-chlorine.html
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Something left a big pile of crap (literally) on my tanning ledge this morning. I'm not sure if it was a raccoon or what, but was wondering if there is anything special I need to do in this case to disinfect the pool? I scooped what I could out with a bucket, which was about as effective as it sounds like it would be, and poured in what liquid bleach I had on hand (3 gallons).
Should I shock this or anything?
Depending on the quality and the amount of the poop, you need to bring your chlorine up to 25ppm. I just posted a new decontamination memo at the Y where I'm the pool operator. Everything you ever wanted to know about poop and vomit, but were afraid to ask.
Scoop out as much as you can, disinfect everything and keep the net in the pool after you shock to disinfect that as well.
Do this at night to give your pool the best chance.
http://www.clean-pool-and-spa.com/swimming...l-chlorine.html
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There seems to be some confusion about the process of "Shocking", so I'll try to clarify. This only applies to Chlorine, not Bromine.
Shocking is nothing more than CATCHING UP when you fall behind adding Chlorine. If you add enough chlorine (which IS Shocking) during/after soaks you should never have to catch up (Shock) when not in use. In other words, Shocking means nothing. You could even say you shock every time you add Chlorine.
If you don't use enough Chlorine (fall behind), your Chlorine Demand will rise, requiring more Chlorine. This is when you hear you need to "Shock". What you're really doing, is Catching Up. There takes a set amount of Chlorine to sanitize/oxidize the tub after each use. e.g. Pay me now, or pay me later. That means you'll have to add that set amount of Chlorine either now or later, but you will have to add it. Better to add it now, than to wait until later.
My advice, forget about the term "Shock". It is nothing more than the addition of Chlorine, which is what you do everyday. Instead learn about Chlorine Demand (CD), in my link below. If you know your CD, you know if you've fallen behind and need to Catch Up. You'll also know HOW MUCH you're behind, and HOW MUCH Chlorine you need to add.
Lastly, if you find you're having trouble keeping up (i.e. during high bather loads), you can use MPS to help out. MPS will help oxidize waste, and break up Combined Chlorine (spent Chlorine). But make no mistake, if you use enough Chlorine, you don't even need MPS. e.g. You can keep a perfectly sanitized tub with just Chlorine, never needing to "Shock".
Thanks for much for the "No Need To Shock" info. I think shocking is, most of the time, a waste of money and time. If you keep your chlorine to the proper level, and everything else, ph, alk. hardness, then there's really no reason to shock. It's way overdone and the only one that benefits from shocking are the chemical companies.
http://www.clean-pool-and-spa.com/swimming...l-chlorine.html
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I have been reading about the saturation index and its importance to keeping my plaster and metals safe from corrosion. However, there seems to be some disagreement as to just how important this really is. Can anyone explain what the Saturation Index is and if it is something that I need to worry about?
An honest answer is that the Saturation Index comes from the Langelier Index which was first used for public water systems. In the 1950's it was introduced to residential pools simply because there wasn't any other index around. Great for your local water company, not so much for pools. Here's where you want to keep your levels:
Chlorine 1.5-3.5ppm
pH 7.6-7.8, not 7.2. You'll use too much acid. pH naturally rises in water through swimmers.
Alkalinity 80-100ppm
Calcium 150-250ppm
I know this may upset some people because they live and die by the Langelier Index and the Saturation Index. Sorry to upset you.
http://www.clean-pool-and-spa.com/swimming...nance-tips.html
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I have noticed the chlorine level has been staying high in the pool despite not shocking or adding tabs to the chlorinator in a couple weeks. I have been waiting for it to come down, but it just is sitting between 8-10ppm. I also use nature 2, so I usually keep it much lower. The pool is clear, filters 8 hours a day, and is used at a moderate level. I confirmed the reading with test strips and by taking a sample to the pool store.
Is there a reason why a chlorine level would stay high for a long time like that?
thanks,
Ray
I agree with chem geek, but lay off the MPS and try using Calcium Hypo. Keep the cover off, and if that doesn't work, you may want to add Thiosuplphate to get the chlorine level down.
http://www.clean-pool-and-spa.com/swimming...l-chlorine.html
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I take care of a pool that is only used (hard) for about 3-4 hours at a shot. The water has a chlorine smell to it. The FC is 3 and available is 3.5. Pool is 10,000 gallons and uses auto feeder with liquid chlorine.
I can't get rid of it. Pool water been tested and is balanced. TDS is kinda high but within limits. Should I just drain some water and refill?
Thanks
If it smells like chlorine, then that means you don't have enough chlorine for the usage and the FAC can't keep up with the use, no recovery time. Probably the chloramine level is too high.
If the water is old, you may do a partial or full water drain. Do this before you shock.
If you have a DPD Test Kit, use it to test for chloramines. If they're over .6-.8, then give it a good shock. 10-12ppm should do it and allow that to sit overnight. If the pool needs to be used soon the next day, you can use Thiosulphate to get the chlorine level down.
http://www.clean-pool-and-spa.com/swimming...l-chlorine.html
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Have been taking care of this pool for a year, and while the water is always clear, I find myself in a cycle:
* pH high, TA low -> Add Muriatic acid
* pH good, TA low -> Add Alkalinity Up
* pH climbing, TA good
* pH high, TA good -> Add Muriatic acid
* pH good, TA low -> Add Alkalinity Up
* pH climbing, TA good
...
It seems that adding Muriatic acid reduces TA (I think I've read it turns it into H2O+CO2+NaCl, jacking up my TDS).
And it seems that either adding Alkalinity Up (Baking Soda) increases pH OR something else is causing my pH to climb.
Anyone have an idea what's going on? Does this go on all year for some folks?
Details that might be useful: outdoor in-ground plaster pool, water clear (no probs keeping it that way, save the above), CYA now ~40, CH=~200, pH range=7.4 .. 8.0, TA range=75..120, trichlor pucks, rarely need to shock, pool open for ~10 weeks now and have been in this cycle ever since, avg temps now ~90F day / 75F night, full-sun most of the day, circulates ~6 hrs/day.
I'm the pool operator at the YMCA in Albany, OR and our fill water is 8.2pH and alkalinity is 30, pretty much what you're describing here. Here's how you do it and it's very simple.
To raise the Alk....Pump off and water motionless, add bicarb to the deep-end. Allow to sit for 2-3 hours, turn pump on and allow to circulate for 1 complete turnover, then re-test. Make another small adjustment if needed.
Lower alk....same procedure, just substitute acid for bicarb.
Raise pH....water circulating and pump on, add bicarb around the perimeter of the pool
Lower pH....same procedure just use acid
Start first with the alkalinity, then do the pH. You shouldn't need to raise the pH too often because pH will naturally rise. Keep your pH around 7.6-7.8. not 7.2.
Most information on how to balance pools comes from your local water company. It's called the Langelier Index, which you've probably heard before. Great for public water systems, not so much for pools. And don't worry about your chlorine not being active enough. At 7.2-7.4pH, your chlorine is about 50% active. At 7.6-7.8, it's 45% active. You're going to be using too much acid to keep the pH at 7.2.
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Hi, I've been using dichlor as a sanitizer in my tub. My question is about shocking. I get a rash when using MPS and I can't use that. Right now I put dichlor in after a soak. Once a week I put in extra to get it above 10ppm. Is this sufficient?
Are you shocking because it's Saturday, or are you shocking because your HT demands it?
What are your readings? What is your chloramines level?
Shock only when needed and if the chloramines are above .6 or higher. This "shocking" thing has gotten a little out of hand, if you ask me. If you keep your dichlor at the right level, take a shower prior to entering the HT, and don't pee in it, then your sanitizer should be able to do its job.
http://www.clean-pool-and-spa.com/swimming...nance-tips.html
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My hot tub has been sitting for 6 months, with water & Baqua Spa. The water still looked clear, then I added a chlorine Shock treatment. Is it possible to switch from Baqua Spa chemicals to chlorine, with out having to drain the tub or changing the water?
If you have water that's been sitting for 6 months and not sure what the water quality is, then drain it and refill. The water could look clear but still harbor bacteria.
http://www.clean-pool-and-spa.com/swimming...nance-tips.html
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can I put a pool salt system on my hot tub.
has always been bromine.
will i need other chemicals?
Yes you can use a salt system in your hot tub. I'm the pool operator at the local YMCA. We have a 1000 gallon HT and have a salt system. The name of the cell is Chloromatic. You can call TMI Salt Pure based out of Washington.
The only other chemicals you'll need are Sodium Bicarb, for pH and alkalinity, muriatic acid, and maybe calcium. Check the pH, alk. and hardness of your fill water first so you'll have a good starting point. You may want to get a salt meter to check the salinity of the hot tub as well. TMI can help with this.
Should I Winterize My Pool
in All Swimming Pools Types
Posted
Yes, winterize your pool properly or you might pay for it in Spring.
http://www.clean-pool-and-spa.com/pool-winterization.html