How Do I Keep My Autofill From Being an Algae Breeding Spot?

[KevMo]

I turned off the water to my autofill for a couple of days to address a non-pool related issue. Before I turned it back on I took the cover off and looked inside. The water was disgusting. I did the OCLT on the pool and I did not lose any chlorine so I don’t think the algae has taken hold in the pool (yet).

I know I can close off the line into the pool and clean it out with bleach and scrubbing. I may have to a mini-SLAM on it to make sure it is all gone. I can regularly fill it with bleach and hand pump out the excess.

The question what do about it going forward since water sets in there all the time? Even when the water to the autofill is on there is a lot of time when it is stagnant. I don’t know if any appreciable chlorine gets in there from the pool.

Here is a picture of the autofill and a comparison of the water within and the pool water.

 

[mas985]

I have used 1" chlorine tabs before. About every week or two does it and it doesn't add much to CYA.

 

[treyrich]

I have started pouring a gallon of pool water into the autofill every time I add anything to the pool, works out to several times per week. It is a bother though, and I would certainly prefer to have a solution that's much more set-it-and-forget-it.

 

[BDY]

I’m interested to know too
I’ve tried to Remember to pour LC in it but it’s always out of sight out of mind

 

[Viper16]

Interesting. I have an autofiller (toilet float valve style), but it sets less than a foot from the wall and ties directly to the wall of the pool. I have it on my irrigation controller and scheduled to weekly. I have never observed dirty water...always appears to have clean water. distance between the autofill and pool could be a factor.

 

[mas985]

Evaporation rate will have the largest impact on algae in the fill bucket. Most fill water has chloramines in the water which helps to suppress the algae for a little while but if the humidity is high and evaporation is low, that water may sit for quite a while before dumping into the pool and that is when algae can get foot hold.