Coral bleaching - caused by RODI?

[Laurenr22]

I've had my 29gallon tank for 2 years now, and recently one of my corals has begun to bleach.
Forgive me, I don't even know what kind of coral this is, but it has been doing great for the past two years. It's mostly a tank for fish but my bf sometimes goes out and buys these coral pieces without really knowing anything about them. ;Facepalm

About a month ago I started doing my top offs with RODI water. Previously I had been using tap water with conditioner.

Is it perhaps not getting enough nutrients? Should I go back to tap water? I do supplement the tank with zooplankton and phytoplankton.

The only other change to my tank has been the addition of a Coral Beauty Angelfish, which I know can sometimes nip at coral, but I haven't witnessed her doing that.

 

[steelwrap]

Stick with ro/di top offs. Tap won't give you nutrients only crap. I'll let someone else answer about the coral

 

[happyhourhero]

Doubtful that it’s from RODI. More likely it’s from swings of either SG, alk, ph, temp with nutrient starved right behind it. Would really need your parameters for a more accurate diagnosis.

 

[Scotty Buttons]

Doubtful that it’s from RODI. More likely it’s from swings of either SG, alk, ph, temp with nutrient starved right behind it. Would really need your parameters for a more accurate diagnosis.

+1

Also what kind of lighting do you have?

 

[Laurenr22]

SG is 1.025
Temp is always 78
Ammonia 0
Nitrates/Nitrites 0
I'm out of test strips for the rest but when I had it checked at the LFS 2 weeks ago they said all was good.

Lighting is just a white and blue LED set from Amazon. I keep it on white from around noon to 6pm, and blue the rest of the time. Off at night. I used to keep it on white from 9-6 but was having algae problems so I cut back. I know it's not the proper lighting setup for coral which is why I haven't purchased too many coral pieces. However it seems to have been fine for the last 2 years.

Can anyone tell me what type of coral it is so I can do some research on it?

 

[happyhourhero]

Looks like a litho

 

[Laurenr22]

Hmm, after searching I think it's a green pavona. It started off as just a little frag and grew over the past 2 years to cover that whole rock. Can I save it? Or is it pretty much done for at this point?

 

[Laurenr22]

Hmm after searching I think it's a green pavona. It started off as just a little frag and has grown to cover that whole rock.
Is it pretty much done for at this point, or is it salvageable? Anything I can do?