Fighting Algae with Borax

[salinda]

It is my understanding that the bacteria that consumes the cya is found in soil in particular. Maybe that bacteria got swept into your pool even with the cover. Not an expert, but this is what I have gleaned from all of the research I have done on it....

[topless]

That's possible, my pool cover setup is almost 20 years old. Back then they didn't concrete the bottom, it's dirt.

[Tredge]

Sorry to hear about your trouble.

The borax is still working miracles for me. My pool maintenance is down a ton...I havent even brushed once all summer!

I do have an SWG though.

When the pool is perfectly still I cant tell if there is water in it or not. Its that clear.

[waterbear]

People tend to forget about a piece of equipment in most inground pools, the hydrostatic relief valve. If you are having a lot of rain and the ground is saturated the valve can open and allow groundwater into the pool. This is one of the ways that they are supposed to work. It can dilute all the chems in your pool and can lead to an algae outbreak, even with a covered pool.

[salinda]

Curious about this: What about areas like mine that have a relatively high water table? My water is pretty perfect but in the winter is when the problem is the worst around here. People get flooding in crawl spaces and such, so the 10 ft deep end of my pool is certainly under the water table. Does this mean the valve is open a lot in the winter? If that groundwater with its cya-eating bacteria is getting in, that might explain the cya losses I have been experiencing every winter.

[topless]

Hydrostatic relief valve? I've never heard of it before and don't know if I have one. Where are they usually located?
This area has gotten so much rain this year that for the first time in the 7 years I've lived here, the sump pump has run, a lot. So, I know the ground is more saturated than anything I've experienced before.

[Sumo1]

Our church pool is drained each year and when it's empty, groundwater comes up through the hydrostatic until it finds its own level. When the pool is full, the weight of the water and the water pressure is enough to keep it closed. The hydrostatic valve is located beneath the drain grate in the deep end of your pool. You have to remove the grate to see it. The valve on the church pool is a 1 1/2" pipe with a cap that is attached with a hinge on one side. There is an O ring below the cap and it is spring-loaded so that the cap is closed when something is holding it down (ie. water/pressure). During the winter, we put a large rock on the valve to slow down the influx of water. As I understand it, almost all pools built in the last 30 years have them, and they are probably required by local building codes in most areas.
Hal