Spa turns green overnight

[calgal198]

Hello all,

So this has happened a few times recently. The rest of the pool is OK but the spa turns green overnight. I made sure filter baskets were clean and test results were good. Ran the filter 24 hours and the problem went away.
We went away for Spring break. Came back after ten days. Everything "looks" great. FC was down to 1 but CC was 0 (my target is 5) and pH is 7.8. I put in a jug of bleach. Next morning the spa is greeen again. ONLY the spa. The pool looks fine.
The results this morning. SPA: FC 1.5, CC 0,, pH 7.8
Pool: FC 4.5, CC 0, pH 7.8, tA 60.

We're having lots of spring stuff fall into the pool. Could that be dyeing the spa??

Now that it's warmer, how many hours should I be running the filter?

What's going on?

Thanks for any help.

 

[cowboycasey]

hmmm, 2 things come to mind

1. Depends on your CYA but I am guessing since you target is 5 your about 30 CYA.. The reason your spa is turning green is because your FC is way below what it should be at FC 5.. Your pool and spa should be the exact same FC.. You should have valves that can change the flow to the SPA and get more chlorine to the SPA.

2. Very unlikely, but do you have metals? this would only make sense if it turned green (water) when you raise the FC, but I thought I would ask.

With a FC of 1 you dodged a bullet with a clear pool, you could have used a float with pucks in it to keep your FC up, yes it would have added CYA but not much in 10 days...

 

[calgal198]

Thank you for your response!

I did put some pucks in but not enough, I guess.

So after the pump running for about an hour, the spa is back to blue.

I will test both spa and pool water tonight and check tomorrow morning again to see.

I think there are some metals floating about as I have weird staining in my pool. I need to test for that.

 

[cowboycasey]

it sounds like your just running out of FC in the spa and algae is taking hold... Because the spa has so much less water and can turn fast your probably going to run into this..

You may be able to cover the spa, less light may help... other than that is run time, maybe split the time you run to 3 times per day at 1 or 2 hours per time.. that would put you at 3 to 6 hours of run time..

See what that does over a couple days and adjust depending on what happens..

 

[calgal198]

it sounds like your just running out of FC in the spa and algae is taking hold... Because the spa has so much less water and can turn fast your probably going to run into this..

You may be able to cover the spa, less light may help... other than that is run time, maybe split the time you run to 3 times per day at 1 or 2 hours per time.. that would put you at 3 to 6 hours of run time..

See what that does over a couple days and adjust depending on what happens..

I will try that. Thank you!