I am still having nitrate issues, I have been doing 10% water changes weekly and the problem has improved since removing the bio balls from the sump, but sill to high. I only have a 20 gal. tub to prepare the water so that is all I can mix at a time, I plan on doing 20 gal changes for the next 3 days to see if that works but want to make sure changing that much in a short time will not be an issue. Some of my corals lookfine, some not so good, the toadstool and finger leather look the worst, my vietnam kenya is not very full but the figi one is fine. The hammer, zoa's and acan all look good. My nitrates are 20 ppm, which I know is way to high for corals. I also switched to coralife salt starting this week from instant ocean in hopes to improve things, not sure it will but after reading some various reviews, instant ocean does not seem to be the best choice for corals, my LFS said the coralife is better and I read some problems with reef crystals which is why I did not go that rote. I am using RO/DI filtered water, it is a bulk reef supply 5 stage unit.