Green Pool !

[VineHouse]

Hi,

We've been using our 10,000 gallon inground, heated, indoor pool for the past month now perfectly, with cristal clear water. I last went in it the Friday before last, and when coming back to check in the next friday (last Friday) I unrolled the cover to discover the pool a horrid shade of green! I don't know what it could be, the chemicals all seem to be balanced, I was using Chlorinate Concentrate, but after reading the pool manual it says that won't clear green water, so I've added 4 pints of Liqued Chlorine in the past 2 days with the filter running continuously. No different.

I vaccumed it yesterday (and took as much water out as possbile), then backwashed. Now the only thing that seems to be a little out of balance is the PH (high) and Stabalizer (low).. I honestly don't know what to do now! I've been recommended (by someone who doesn't even own a pool!) to Shock it with Bio Shock (but even after 4 pints of liqued it's no clearer) and I'v read te Bio Shock can make it go white/cloudy?

ANY advice greatly appreciated!

[Backglass]

Do you have a well? Sounds like copper in the water to me. Test for metals.

[Buggsw]

I don't thing it's likely metals. Usually you don't see green or brown with that until you add chlorine. It's the chemical reaction to the metals in the water. Otherwise metals are not detectable in water to the naked eye.

4 pints of liquid chlorine over 2 days is certainly not enough chlorine for that volume of water. 4 pints of 6% bleach will only bring it up to 3 and that's only if there is no algae. 4 pints of 12% liquid chlorine will only bring it up to 6. You need to bring it to shock level and keep it there day and night until it stays at that level all night long. So you may have to add more several times a day to keep it there. Your shock level will depend on your CYA level. If your CYA is 0 your shock level would be 10. The higher your CYA the higher your shock level needs to be. Keeping it so low, is getting burned out by the sun and being used up before it kills all the algae, so the algae keeps multiplying and keeping the water green.

We'd really need a full set of readings, including your CYA (stabilizer) level in order to advise dosages of anything.

[VineHouse]

Thank you both for your very prompt replies !

I added another 2 pints yesterday, as well as brought the PH back down to where it should be with some acid. All chemicals seem fully balanced now, apart from the chlorine which is now very high!

I spoke to my local pool store (in England), she said she'd recieved hundreds of phone calls over the past week from others with the same problem, and she claims it's due to bad weather? (we've had very odd/bad weather over the past 2 weeks, including a very rare small tornado! along with much rain/wind/thunder)

As it's indoor, I don't see how this could affect it? And if that's true, any idea on how long it'll stay like it is? (I can upload pictures if you like)

Backglass, we do have a well, but the water supply for the pool is mains?

Thanks again both.

[Buggsw]

Egad, it's an indoor pool, I totally missed that. You really don't want to use CYA in an indoor pool so forget what I said about CYA.

Goodness, a tornado? Isn't that uncommon in England? I grew up in tornado alley in the midwest of the USA. You must be having some warm, humid weather.