Opened pool yesterday - green layer!!

[19redwings]

3 weeks ago a used a spare sump pump to pump about 3-4" out to get the level down and the water was clear and the bottom was clean.

I took the cover off yesterday and there was a 1/16-1/32 layer of algae from the waterline down EVERYWHERE. I have a 'real' test kit ordered yesterday so all I had was the strips and everything was low. I dumped in 4-1.5 gallons of 6% bleach and a bottle of concentrated algaecide. I had time to brush the shallow end before calling it a night.

This morning where I brushed was clean and the water appears to be clear. Strip reveals everything ok, except pH and stabilizer are a little low. Leaving the pump running (I have to fly out today, return tomorrow night) and I should be able to brush the deep end before I leave.

Hopefully my test kit will be here when I get back!

 

[AnnaK]

According to the Pool Calculator you'd need a little over 7 gallons of 6% bleach to raise FC from 0 to 15 to kill what's starting up in there. The 4 1/2 gallons are better than nothing though.

I found brushing to be a critical item last year when my pool turned into a swamp. Sounds like you probably caught it in time. The triage you were able to do before having to leave will help it limp along until you can give it your full attention.


AnnaK

 

[19redwings]

Thanks for the response. It was qty 4 1.5 gallon jugs, so I put 6 gallons in. I will throw in another 1.5 before I leave.

Thanks again!

Bill

 

[JasonLion]

Having a good chlorine test so you can know the FC level makes this process much simpler. How much bleach you should add to day really depends on how low the FC fell overnight. You can make some progress with guess work but you risk either using too much chlorine or not killing all the algae.