Yellow tang / Red Slime

[del_rn]

I have a 70 gallon tank with 55 lbs of LR in it. It has been up and running since Jan 08. I have a coral beauty, yellow tang, occ clown, pink and blue shrimp goby, lawnmower blenny, long spine urchin, and several shrimp and hermit crabs. I have recently been battling red slime. I have treated the tank with Chemi clean 3 times now over the course of 3 weeks. When the red slime started showing up, I noticed my yellow tang turning orange, then later he started showing signs of HLLE. I have been feeding him emerald entree, formula two (both frozed), formula one & two pellets, geen and purple seawead. I have fed enriched brine shrimp on occassion and for my other fish. I have been soaking the food in garlic and selcom for about 2-3 weeks now. I am not seeing much improvement and I can't keep the red slime gone. I do 10-15% water changes every 1-2 weeks. Ph is 8.3, 0 nitrites, 0 ammonia, 20 nitrates, salinity 1.024-1.025. I have 2 75 gallon bio wheels running, a protein skimmer, and I just got a ground to put in the tank. Any suggestions??? Please help me solve this mystery. The tang is eating well, he does have rapid gill movement, and he is still slightly orange tinted.

 

[del_rn]

I just retested my water. Ph is 8.3, 0 nirtrite, 0 nitrate, 0 ammonia, salinity 1.025-1.026, phos 0. I forgot to mention that I have a 900 power head in there as well. I read the post on the cynobacteria and I am going to reduce the lighting time and work on that however I need help with the tang. I have moon lights on at night, will that help the cyno to grow too?? How long should I leave my lights on during the day?