green water - I don't think anymore algae

[mbar]

It sounds like you do have algae, if you are losing chlorine that fast, something is probably eating it up. I would get rid of the algae first by getting your chlorine up to shock level and keep it there.

Stabilizer . . . . . . Min. FC . . . . Max FC . . . 'Shock' FC
=> 0 ppm . . . . . . . 1 ppm . . . . . 3 ppm . . . . 10 ppm
=> 10 - 20 ppm . . . . 2 ppm . . . . . 5 ppm . . . . 12 ppm
=> 30 - 50 ppm . . . . 3 ppm . . . . . 6 ppm . . . . 15 ppm
=> 60 - 90 ppm . . . . 5 ppm . . . . . 10 ppm . . .. 20 ppm
=> 100 - 200 ppm . . . 8 ppm . . . . . 15 ppm . . .. 25 ppm

With a cya between 30 & 40, you need to get your chlorine up to 15ppm, and keep it there until you can hold it overnight.

You can test if the stain is mineral by putting some crushed vitamin C in a sock and rubbing it on the stain. If the stain lightens or goes away it is mineral, if not chlorine should take care of it. You can also use some ph down in a sock the same way as the vitamin C.

[waterbear]

I agree with MBar. If the FC is not holding something is eating it up. Metals don't do that. Take care of the chlorine demand first and then worry about treating the stains.

[edarling]

OK - I am dealing with algae filtering first, then the stains. The stains really bug me though The water is much clearer today after another day of 15 CL, so I'll wait a few more days before moving on to the stain. Thanks.