What effect does UV have on corals?

[jerry26]

sounds like he may be talking about SE bulbs. i would have issues with them bleaching but i recently bought some newer frags and have been playing with the acclimation process a bit and after 2-3 weeks, they still have not bleached. buuuttt.... they are closed up kinda funny. one of them is peach zoa or something like that and its closed tighter than ever usually. the other is a eagle eye zoa and its partially closed.(part of it is completely closed, part is completely open). another zoas ive had for a while just up and bleached out of nowhere but still opens and looks fine now. some palys frags ive had for a while, which has gone from 4 polys to 7 on one frag with two others doing similarly, suddenly appear irritated. i think those little copepods scurrying all over the place are just irritating them. ive watched alot of videos of them on irritated coral and read alot about them being irritators. not harmful, just irritating, like a vermitid snail.

 

[jerry26]

I know theres reef crystals, red sea and some kent stuff And more i cant recall but idk the specifics off the top of my head. I never really considered the salt since i dose(manually) but idk, something im not seeing is out of wack.

Well my ego has gotten the better of me on this one it appears. I found what is out of wack. Its nitrates. Ive been experimenting with gha scrubbing and everything was going good and to be honest i was starting to think my test kit was broke because ive NEVER detected any nitrates in my water. That lack of detection has apparently made me overlook nitrate testing and now its biting me in the you know what. The test i just took shows 80(ppm?). Tomorrow ima buy some reef crystals and do a major water change. I think this is the first time ill exceed a 20% WC. Since im so lightly stocked i think im gonna just do weekly water changes and see how my params hold instead of dosing. I have to admit, im kinda glad to be seeing nitrates though. Sometimes i felt like my tank was too clean.