Using Algaecide as a preventative.

I read here that algaecides are better to use as a preventative measure than a treatment. I never had an algae problem with my pool – only in my 2nd year. I added one dose of poly-quat algaecide two weeks ago. My question is how often do you need to add algaecide using it as a preventative measure? Does it dissipate over time? Since there isn’t any test I know to measure levels I thought someone here might have some insight. Thanks

I don't use it at all. There was a time this year with two days of swimming with sporadic rain and no bleach added that the water started to cloud up a tiny bit. I added some then, along with shocking the pool and after the second day it was clear again. I don't know if I needed to add it or not, I just figured that it was the start of an algae bloom.

I don't use it in my pool, but Ben has said in the past that it will eventually filter out of your water. I believe there are some forum members that add it every couple of weeks, hopefully somebody that uses it will chime in here.

Janet

I use a polyquat every other week (the recommendation on the bottle says every week, but I ignored that). I've never had an algae problem in 3 years, but then I only got seriously involved in the PoolForum recently. It looks like maintaining a sufficient chlorine level is enough to prevent algae, but using an algaecide will prevent any "accidental" drop in chlorine, even to zero, from producing an algae bloom. That's the main reason I use it -- I'm pretty diligent about adding chlorine, but I have had at least two times where I let the chlorine drop too far (close to zero) -- and fortunately, had no problems.

Some people are investigating using Borax not only to raise pH, but to maintain a level of Boric Acid in your pool that presumably is an algaecide as well (it also acts a little like a pH buffer, similar to the carbonates). Evan (waterbear) is currently investigating what exactly the "ppm Borate" means on test kits since we currently have conflicting information from different sources.

Richard

I have been adding 3-4 ounces of poly 60 every Sunday for the last 2 years. Pool has been perfect:) Can't thank the folks on this forum enough for getting me there. Ran my cl levels around 5-7 last yr b/c cya was high. Run cl this yr b/t 3-5. As chem geek mentioned an accidental drop has not caused a problem. I am probably over cautious b/c after dealing with Mustard Algae in the past I am paranoid;)

It certainly doesn't hurt to use it, but actually, if you just maintain proper water chemistry, you don't need it. I never use it except at closing in the fall, and then I add a double dose.