quantumchromodynamics

The solubility of silver is dependent on the level of bromide, not bromine. If you add 0.5 ounces of sodium bromide per 100 gallons on fill up, that starts you out with 16 ppm bromide. That means that a silver level of 291 ppt (parts per trillion) will saturate the water with silver bromide. For every 10 ppm of bromine that you add from bromine tabs, your bromide level will increase by 5 ppm. The solubility product (Ksp) of silver bromide is 5.4 × 10^-13, which is very low. The solubility product is the product of the molar concentration of silver x the molar concentration of bromide. 107,868 ppm of silver = 1 mole per liter of silver (1M) 79,904 ppm of bromide = 1 mole per liter of bromide (1M). ________________________________________________ Example 10 ppm of bromide = 1.2515 x 10-4 moles per liter 5.4 x 10-13 = (1.2515 x 10-4M)(molar concentration of silver) The molar concentration of silver is 4.3148 x 10-9M The concentration of silver in ppm is 4.65 x 10-4 ppm, which equals 465 ppt. _____________________________________________________ On startup, your level of bromide will be 16 ppm, which will limit the silver concentration to 291 ppt. The concentration of silver is too low to do any good. All other silver ion products specifically say that their silver ion product is not compatible with bromine/bromide. I recommend a minimum level of bromine of 1.0 ppm at all times. Note: This is not a target level, it's just a minimum. I recommend that you maintain about 2.0 ppm to 3.0 ppm on startup, about 2.5 ppm to 3.5 ppm after 30 days of using tabs, about 3.5 ppm to 4.5 ppm after 60 days of using tabs, and that you change the water at least by 90 days. The progressively higher levels of Total Bromine are to help compensate for the increasing levels of dimethylhydantoin from the tabs. Periodic shocking with regular, unscented 6.0 % bleach or MPS can help eliminate any bromamines that might have accumulated. Since there is no readily available test for bromamines, you should carefully monitor your bromine demand and compensate accordingly.

Aerate until your pH gets to 7.9 and then add enough 31.45 % muriatic (hydrochloric) acid to lower it to 7.1. Continue to do this until your TA gets to about 100 ppm. Then allow the pH to settle at a level to see if you need to lower the TA any more, or leave it at 100 ppm. A calcium of 100 ppm is fine, I would leave it there. You can get muriatic acid from any hardware store You can use the the pool calculator to calculate your CSI and to determine dosages of chemicals to add.

I really don't see the need for the patent, or the additional ingredients. It seems to me that they are going out of their way to make it seem like they have created something new and different. At best, they have figured out that MPS can convert some chloride to chlorine in a high salt environment. They refer to it as an "invention". I don't see how they have invented anything. All they're doing is mixing different spa chemicals into one product. That's not an invention. I think that the added ingredients are mostly counterproductive. They can be added separately if necessary. They are more likely to mess up the chemistry than help. The MPS is the only thing that is doing anything, and even that is not necessary. Their primary claim is the creation of chlorine on demand, which can be achieved with sodium hypochlorite.

I recommend that you get the Taylor K-2006 test kit (FAS-DPD). This will allow you to test FC (Free Chlorine) and CC (Combined Chlorine) to a precision of 0.2 ppm or 0.5 ppm. You should maintain about a -0.3 CSI (Calcite Saturation Index) to prevent scaling in the salt cell. You can calculate your CSI by using the the pool calculator As long as your chlorine demand is not excessive, and you don't have any CCs, then you don't need to shock. I recommend that you use your salt system to provide the baseline chlorine demand and that you use chem geek's rule of thumb for additional oxidizer based on usage. Chem geek's rule of thumb regarding the addition of oxidizer is for every person-hour of soak time you need to add 3.5 teaspoons of dichlor or 5 fluid ounces of 6% unscented bleach or 7 teaspoons of 43% MPS. This can be helpful in determining the correct amount of oxidizer to add. This is just a starting point. You will need to adjust the amounts based on your test results. With the salt system, you should need somewhat less than the aforementioned amounts. The key is to maintain about 2 to 4 ppm FC and less than 0.5 ppm CC (Ideally, CC should be kept at zero). You should test before you soak and the level should be about 2.0 ppm FC with no CC. I recommend that you use dichlor until your Cyanuric acid level reaches 20 to 30 ppm and then switch to liquid chlorine or MPS. For liquid chlorine, you can use regular, unscented 6.0 % bleach (sodium hypochlorite). Once you get cyanuric acid in your water, you should maintain a FC of about 7.5 % of your Cyanuric acid. MPS will probably increase your chlorine levels if you use it, so you should be careful not to add too much. It can also register on the CC test. There is a special reagent that you can get to remove the MPS CC interference. I recommend that you read the following: Nitro's approach to Water Maintenance Dichlor/bleach Method In A Nutshell Chlorine Demand

This patent indicates that MPS can oxidize chloride to chlorine at a measurable rate when the salt level is elevated, such as in a salt system. Reference 1 Reference 2

The solubilities of DCDMH, DBDMH and BCDMH are about 500 ppm to 2,000 ppm (depending on data source). The bromine and chlorine hydrolyze in water and the DMH is left. DMH is more soluble in water than BCDMH (one reference shows 4,516 mg/l). http://en.wikipedia.org/wiki/BCDMH Silver is not compatible with bromine. Due to the low solubility of silver bromide, it is not possible to maintain sufficient silver levels to be effective. Silver levels will typically be in the ppt (parts per trillion) range. 1 ppt = 1 millionth of a ppm. For example, silver bromide will be at saturation when the bromide level is 10 ppm and the silver level is only 0.000465 ppm = 465 ppt (parts per trillion). Studies indicate that silver should be in the 20 to 40 ppb (parts per billion) range to be effective. Note: Silver in drinking water is limited to 100 ppb. There are no studies that indicate that less than ppb levels of silver have any antimicrobial effect. Maintaining 1 to 2 ppm of bromine is generally safe as long as the level is kept consistent and the level of dimethylhydantoin is limited.

The rate of dissipation of the MPS will depend on the oxidizer demand. If there are a lot of organics to oxidize, then the MPS will be consumed fairly quickly at hot tub temperatures. If there are not a lot of organics to oxidize, then the MPS should last longer (perhaps 24 hours). I think that you would be OK as long as you limited the amount of MPS to 1 ounce weight per 500 gallons of water and waited 1 hour before going in. I think it is better to add the MPS after soaking and based on chem geek's rule of 7 teaspoons per person hour.

Ok, so the CX means that the motor is a PSC (Permanent Split Capacitor) switchless design. Your capacitor is a "Run" capacitor. There is no "Start" capacitor. Since there is no start capacitor, the motor will have significantly less starting torque than a capacitor-start motor. Any excessive resistance could keep the motor from starting. You can check the impeller for debris by removing the pump basket and sticking your finger into the hole going to the impeller. The impeller should be clear of debris and easy to turn. Make sure that the pump can't turn on while you are reaching in by turning off the power at the circuit breaker. Even though the motor is called "switchless", I still think that there might be a switch under the end cap that might need to be cleaned. That would be the next step if nothing else works. I'm not sure that there is a switch. The motor is called "switchless", so perhaps it doesn't have one. The capacitor is involved in starting, so that is the best place to start. The above reference gives other things to check. The reference shows how to check the capacitor, windings and the protector (Thermal Overload).

Those chemicals soften the water by forming insoluble calcium compounds. The calcium precipitates out as a granular powder, and as scale. I recommend against trying to remove calcium this way as it makes a mess and could scale the tub and equipment. You can manage the CSI by keeping a lower carbonate alkalinity and/or a lower pH. Adding a metal sequestrant could also help. If you want to reduce the calcium level of your fill water, then you should use a water softener.

10 ppm should be fine for a shock. Keep the cover open to allow any gases to get out. Silver is not compatible with bromine due to the low solubility of silver bromide. Chem geek's rule of thumb regarding the addition of oxidizer is for every person-hour of soak time you need to add 3.5 teaspoons of dichlor or 5 fluid ounces of 6% unscented bleach or 7 teaspoons of 43% MPS. This can be helpful in determining the correct amount of oxidizer to add. If you have an ozonator, the amounts will generally be less. The key thing is to maintain a consistent bromine level and to never allow the level to drop below 1.0 ppm. Test frequently and maintain a consistent 2 to 5 ppm. Read waterbear's post on how to do bromine properly. Waterbear's post I think that there should be a correction factor for the level of bromine and for the shock level for bromine due to the dimethylhydantoin concentration. DMH (Dimethylhydantoin) is the carrier chemical in bromine tabs similar to how cyanuric acid is the carrier in dichlor or trichlor. DMH builds up over time and reduces the reaction rate of bromine in a similar way to how cyanuric acid reduces the reaction rate of chlorine. The problem is that we do not know the equilibrium constants to determine the correct ratios. I recommend that DMH be kept to less than 100 ppm (Others show 200 ppm). I recommend that the use of tabs be minimized and that the water be changed at least every 3 months. As the level of DMH increases, I recommend a slightly higher level of bromine and more frequent shocking. ______________________________________________________ Note: Monobromamine is nearly as active as free bromine due to the presence of the monobromammonium ion. NH2Br + H+ < > NH3Br+ The equilibrium constant is 3.2 x 10-7 at 25o C. pK = 6.49. Reference 1 Reference 2

The "U" is actually the Greek letter Mu ("µ"), which means micro, which means one millionth. You have a 30 microfarad capacitor (30 µF) = (30 MFD). Make sure that the size dimensions match up. I think that there is a switch in the back under the end cap. You have to remove the 4 long through-bolts and pull back the end cap to get at the switch. If the pump is old, the through-bolts can break due to corrosion and the torque from the bolts being so long, and you might not be able to reassemble the motor. Make a mark on the end cap and motor to make sure you can realign the end cap so that the through-bolts line back up with the holes. Before removing the end cap, replace the capacitor, and check the impeller for debris to see if that will work. Sometimes the impeller will get clogged and that can create enough resistance to prevent the motor from starting since it has less starting torque than normal. What does your motor label say for "type"?

You can get capacitors at any motor shop. Look under electrical motors online or in the yellow pages.. That type of motor uses a centrifugal switch for starting. On startup, the switch is closed, and as the motor reaches speed, the switch opens. Over time, the switch contacts get oxidized and don't make good contact. Clean the contacts of the switch.

The above reference patent specifies that a chelating agent is needed for the silver to be effective. However, if the silver is chelated, then I don't think that it will be active. Another patent You could probably get EPA approval for a sand and bromine system because the bromine is doing all of the work. It is also important to note that the highest possible concentration of silver is limited by the bromide ion concentration. For example, if the bromide ion concentration were only 1 ppm, then the silver ion concentration could be maintained at about 4.65 ppb (parts per billion). However, if one were to add sodium bromide initially, then the bromide ion concentration would be much higher and would significantly limit the silver concentration. In their patent, they do not initially add sodium bromide to the water. That would allow them to maintain the 1 to 3 ppb levels that they claim. However, once the bromide levels increased, the silver ion concentration would drop significantly.

Also note that all of the other silver based systems, such as Nature2, specify that their system is not compatible with bromine.

I would avoid silver in a bromine tub due to the low solubility of silver bromide, which is only 140 ppb (parts per billion). Solubility product, Ksp 5.4 × 10-13. For example, if the bromide concentration were 79.9 ppm (0.001 M), then the water would be saturated with silver bromide when the silver concentration reached 5.8 x 10-5 ppm (58 parts per trillion). I would think that the silver would never reach a concentration sufficient to do any good.

For anyone interested in learning more about chemistry, you might want to check out Khan Academy, where they have videos on various subjects, such as this video about chemical reactions in equilibrium.

It's just a typical salt system. They are just trying to be clever by calling the cell a "hydroxinator" because it creates hydroxide just like every other salt cell. They are trying to convince people that the hydroxide is the key benefit. Their claim of creating "magnesium hydroxide" is nonsense. The concentration of hydroxide in the general water is determined by the pH. Their claim of creating some sort of special chlorine is also nonsense. Chlorine is constantly changing from hypochlorous acid to hypochlorite to chlorinated cyanurates. The amount of time chlorine spends as each type depends on the pH and the cyanuric acid concentration.

Replace the housing gasket, diffuser gasket and the seal assembly. Check the seal plate, impeller, diffuser and impeller ring and replace any that are bad. Check the impeller threads to make sure that they are not stripped. http://www.hayward-pool.com/pdf/manuals/Manual258.pdf

Sodium bisulfate can be found in any pool/spa store. It is sold as dry acid. It is a granular form of pH down. I prefer muriatic acid instead of sodium bisulfate.

A pressure washer should not be used. The pressure is too high and could damage the fabric. You should clean your filters according to the instructions here. Most TSP that you will find locally is not real TSP, and does not work as well as real TSP. You can get real TSP here. You should get a second set of filters so that you can allow one to soak while using the other set.

The clarity of a salt pool and a non-salt pool should be equal. There is no such thing as a "chlorine tint".

One of the issues with using salt in a plaster pool is that plaster needs a neutral to slightly positive CSI to get maximum longevity out of the plaster, while the salt cell needs a slightly negative CSI to get optimum results. My opinion is that if you use a salt system on a plaster pool, then you will have to compromise on one or both of these things.

Here is my most recent post with chemistry information. Post a link to anyone who has said the same or similar thing. How much of the chemistry information that you post is a result of your original research? What chemistry information have you posted that has not been posted by others?

Hmmm...interesting. Here is someone giving an easy answer, and you're like "Hey, wait a minute. That's not good enough. That's not acceptable. I want to see the research that backs up their opinion about the 200 mg/l limit." Notice that you refer to it as their "opinion", not as a fact. You are not willing to accept it until you see the chemistry for yourself. You find it deeply unsatisfying that someone just gives an answer without providing any explanation or science. This proves my point.