Bulbs are only a few months old. You are correct about the phosphate. I have recently reduced them from 3 to .3. I have ordered PhosBan & it should be here in a couple of days & hopefully that will help. Got 2 boxes of salt for more WC. I will test the phosphate of the freshly mixed SW.
We had a horrible flatworm issue and used flatworm x twice. Made sure to perform large water changes afterwards. And prior to the medication, we had to vacuum as much out as we could. WHAT A PAIN! I feel for ya! Good luck