To drain or not to drain pool with high CYA?

[stevemac213]

Ok, what about cleaning the filter....should that be done now, or after it's filled...or not at all?

Thanks.

[PoolDoc]

What type of filter do you have?

[stevemac213]

It is a Purex Triton Cartridge Filter CC320P. I cleaned it a few months ago...the cartridges were black.

Question...I put all my info in when I signed up but not sure where it went...any idea?

Thanks.

[PoolDoc]

You should clean your cartridges -- how-to here: Cleaning-your-Cartridge-Filter-without-Damaging-It!

No idea about the data.

[stevemac213]

Ok, cleaned the cartridges and let them soak in TSP overnight. They look good and got rid of lots of green...will I need to do this again after I fill it up and run the pump, due to algae that was in the pool?

Have drained more than 3/4 and have noticed some black spots on the bottom and near the stairs...looks like black algae? Thinking about draining it all.

[PoolDoc]

Scrape the spots with your fingernail, then smear the crud on a white 3x5 card (or similar) -- black algae smears dark green.

If it *is* black algae, I'd recommend pressure washing first, and then pouring plain household bleach on all spots. Wait till late evening, and then pour bleach liberally over all spots

Be careful, when pressure washing, to NOT strip the plaster. Old or soft plaster can't take a lot of pressure. Also, try to refill ASAP -- being dry is BAD for plaster, especially old plaster. You're in California -- lots of sun & dry air. You may want to set up a couple of sprinklers or misters on a timer to keep the pool walls damp.

[stevemac213]

Thanks Ben. I really don't want to pressure wash it because it is too old, (1986). I know it needs re-plastering but want to try and get a couple more years out of it. I did what you said and it is definitely black algae.

Would it hurt the plaster to pour bleach directly on the spots? I heard that you can also rub a 3" Trichlor puck on them. I am going to try and work on them now and then start the refill. Should I be pouring bleach in at nighttime when refilling, even though the pump is not running?

Thanks again.