My Hayward 220 Filter with a 1hp Hayward pump on a regular basis (1x-2x weekly) after running ok for a few days, shoots tiny bubbles out of both returns. I run the filter approx 6hrs daily
To cure this I backwash the filter and the bubbles go away, all runs ok for a few days then the bubbles reappear
There is usually no increase in pressure ( before then after backwash) , it always seems to run at 10psi. The waste water is very pale brown but not what I would call super dirty
This occurs if I add a 1/3 cup of DE or if I do not
Is this normal ? not sure where the problem could be.