Need some help small zoos still looking bad

[Jyetman]

I have a bucket scrubber with a weak water fall. It grows lumps of hair algae when harvested size of baseball in 1.5 weeks time. Also have thick mat of grape culurapa under waterline. My API kit shows zero so upgraded to a salifert kit thinking need more precise measurements. Still shows clear zero PO4 what is going on why can't I get a .03 PO4 for proper coral growth? Algae still grows on glass and rocks not in abundance though but does this mean I still have PO4?

 

[Jyetman]

Blue cloves shriveled and small colorful zoos are half closed no pests been doing this for years they close short time slowly open back up. The big ugly looking zoos are doing fine so are my blastos, acan, Kenya tree, montipora plate, GSP, duncans and yellow polyps. My Tank age is nearing the 5 year mark. Started doing KALK drips several months ago to maintain ALK and Calcium using single doser slow drips for 40 second every 4 minutes. All my tests are in the proper ranges Calcium @ 440 PPM, ALK 9 DKH, MAG 1490 PPM, Salinity 1.025 Refractometer and Zero Nitrates. Removed all algae from scrubber screen a week ago to see if PO4 would increase still reads zero zoos slowly opening but look bad. Not sure what to do next?

This is what my green zoos look like and others very similar. They open in the morning and by mid afternoon half start to close up. Over a year ago I bought a single Armor of God polyp. It use to be the size of a nickel but closed up and five months later opened. Never got large again but grew seven others. Those seven would open and close periodically but in time reduced down to two polyps. I just don't understand what is going on other corals seem to do fine. I gave up on water dips because those closed polyps would get worse and die besides nothing came off them. If my PO4 kit reads zero could that be the problem?

 

[650-IS350]

what lighting are you using? is it newly introduced to the tank?

 

[Jyetman]

what lighting are you using? is it newly introduced to the tank?

No have a 160 Watt maxspect 10k razor which is now two years old. I started low and ended up a year later at A:81/B:100 10" off waterline. Also supplementing single T5 24" ATI Blue bulb thinking maybe related to lack of spectrum from LED.