Corals bleaching. One SPS and few LPSs.

[A.Percula]

Hey guys,

I am trying to get advice on coral bleaching. I know it could be many reasons, but I have a birdnest that is getting bleached and a few LPSs (especially chalice and favia).

I suffer from low nutrients, my nitrates were around .20ppm for a month. I reduce phosphates with Phosbond (white pellets) and kept it at .02 ppm (it fluctuates from .02-.07.ppm). I am not sure what is the best way to keep a stable phosphate.

A week ago I started dosing Nitrates. And I add 4 ml of Reef Energy daily. I also changed my lights from two prime hd to one radion g4pro, with reduced intensity. I am not sure if the change was too fast for them. My tank is an IM 40.

Any advice on how to get them recovered?

 

[RobZilla04]

Dial back the light intensity. Remove the Phosphate binder. Test all parameters to see if something is outta whack.

Water change is usually a good start once you've done the above.

 

[markalot]

Stop controlling Phosphate for now, it will kill corals every time. Stop testing for PO4, be happy, worry about it once the tank is stable and only if you see issues. High phosphate rarely kills corals.

Make sure your Alk is stable, and I recommend the lower end, 7.0 is a good target IMO.

You made too many changes at once, that's a problem as well, especially for acros, but the LPS are most likely suffering from rapid PO4 reduction.

With these smaller tanks algae is going to be an issue, so I understand why you want to control Phosphate, but it's going to be tough to keep nutrients low AND healthy corals. Just remember stability is the key. If you need to run low PO4 you can do it but it must be stable. If it rises slowly then you'll need to drop it slowly.