Culator -- Solution or Just Another "Pool Store" Product?

[mbar]

I really do think it has something to do with calcium too. The first year I had staining, the pool store had me dump in lots of calcium. I did a stain treatment and ended up with a pool full of milk. Then they had me use a flocking agent - and turn the filter off for 2 days. After the water cleared up I did not have any stains for the rest of the year. The calcium did drop a lot if my memory serves me right. Then I went a couple of years without using calcium as I thought it was not necessary. I had a lot of staining at this time, and learned how to get rid of stains very well!!! Then l read where a fiberglass pool needs calcium to keep something (I am not good at any chemistry as you know) from leaching out of the gelcoat, maybe cobalt? So I started using some calcium. Last year, I know I posted it, my pool was all balanced, the water very clear, but there was a greenish tint to the water that I could not get rid of. I put enough calcium to get it up to 300, and right before my eyes the water turned blue! I had no idea why or how it happened. I didn't think it was a coincidence, because it was an immediate reaction to the calcium. I did notice that when I added bleach to the water, I could see the water cloud. I think I even asked you about it. Once the bleach was circulated the cloud dissipated. Now this year it happens again - but I have not had one stain since I treated the water at the start of the season. My pool has been holding chlorine, the ph raises with the bleach so I add a puck because I hate the muriatic acid. I have not used anything else in my water and my pool is white! I have a couple of bottles of sequestering agent and some ascorbic acid sitting on a shelf - I love it. I do have the culator in the skimmer basket too - so I don't know if it has anything to do with it. We'll see next year when I open. My pool always opens with no cya, and low ph. I try to add bleach under the cover when we have a couple of warm days, but basically I am starting from scratch every year. I live in the middle of the woods so my water gets full of so much stuff I don't know where the metals come from. I also have a well and a heater- that's why I gave up trying to figure out where they came from and just concentrated on getting rid of them. It would be so great to just have a milky pool at the beginning of the summer and once cleared up not to have stains! Maybe this is it???

[JimK]

I realize this thread hasn't been active for some time, but I stumbled across it when researching less expensive/better options to prevent metal stains (iron I believe) on my vinyl pool. For the past several seasons I've been using Jack's Magic Purple Stuff and I've not had any staining since. However, it costs me about $200 a season (per instructions I add 2qts at the beginning of the season, then 12oz a week to maintain the recommended level).

I'm intrigued by the idea that maintaining higher calcium levels may prevent staining. Any updates on this? Has it been determined that higher calcium works? Any downside to this method?

Any further information on whether or not the CuLator actually works?

For reference, I have a 20k IG vinyl salt water pool, DE filter, and using a SWCG.

Thanks.

[waterbear]

The higher calcium is for fiberglass pools. There is some empirical evidence that it helps lessen iron staining and cobalt spotting which fiberglass pools are prone to more so than other pool surfaces.

[PoolDoc]

I very much doubt that the calcium is directly preventing staining.

I suspect that what is happening is that you are creating fine calcium precipitates in the filter, which because of flow and surface area tend to get 'stained' BEFORE the pool does.

If my analysis is correct, this is directly related to the method I've mentioned of using cal hypo to remove metals from the water.

[JimK]

The higher calcium is for fiberglass pools. There is some empirical evidence that it helps lessen iron staining and cobalt spotting which fiberglass pools are prone to more so than other pool surfaces.

I very much doubt that the calcium is directly preventing staining.

I suspect that what is happening is that you are creating fine calcium precipitates in the filter, which because of flow and surface area tend to get 'stained' BEFORE the pool does.

If my analysis is correct, this is directly related to the method I've mentioned of using cal hypo to remove metals from the water.

Thanks.

[waterbear]

I very much doubt that the calcium is directly preventing staining.

I suspect that what is happening is that you are creating fine calcium precipitates in the filter, which because of flow and surface area tend to get 'stained' BEFORE the pool does.

If my analysis is correct, this is directly related to the method I've mentioned of using cal hypo to remove metals from the water.

IF that is the case then perhaps this is an easier way to achieve this. I know of others with fiberglass pools who have done this and had similar results. One thing that I did notice is that one time when I let the calcium hardness drop (I fill with softened water) I got stains again. My fill water has no iron (my city water is reverse osmosis where I live and very soft. They add calcium to bring the hardness up some and my house also has a water softener. I suspect the iron was introduces by "pool salt" since the first stains I every saw were in the spot the salt sat to dissolve.)

[PoolDoc]

Waterbear,

I don't see how having DISSOLVED calcium would help; maybe there's some sort of ionic effect that raises the staining threshold. If so maybe Chem_Geek has some info on that. But what I've pretty much confirmed is that if you make the water PASS THROUGH calcium particles, especially in a high oxidizing state (ie, cal hypo via the skimmer) you WILL stain the heck out of the goo on the filter.

Now, if you are precipitating calcium onto the filter, maybe THAT will help.

[chem geek]

I don't see where doubly positive calcium ions are going to help precipitate doubly charged positive copper or triply charged positive iron since these will repel each other. I think Ben's explanation is more likely since adding Cal-Hypo into pool water that is already close to saturated with calcium carbonate will cause both the CH and pH to go up substantially causing calcium carbonate to precipitate. The higher pH will cause the metal ions to form metal oxides-hydroxides so they'd all precipitate together into the filter.

In theory, just raising the pH should precipitate the metal, but perhaps it's normally super-saturated and needs something to help its precipitation, such as calcium carbonate. This is all just an educated guess, however.