SPS Slowly Bleaching

[IFbettas]

Hey everyone. While I had great success with sps corals in the past few years, after I moved a few months ago and re-setup my tank the results haven't been very good.

Every time I get new frags, they do really well for about a month, growing and holding good color. After that many of them slowly start losing color and the polyps stop opening much. They eventually reach an extremely light shade of their original color, almost white, and the growth stops. None have died, but they don't look very good. There are some that are doing well, but most are showing the symptoms described above.

I think I might've found the problem tonight, but I want to check what you guys think. On my old Alk test the alkalinity was ~9 dkh, but after getting a new kit I found out my Alk is really at ~6 dkh (I verified the results with a different kit). I'm thinking this low alkalinity could be the problem, but here are my other parameters (salifert test kits):

SG: 1.025
Cal:400
Alk:6 dkh (the problem?)
Mag:1200
PO4:0
NO3:5
PH: 7.9-8.0

My tank is not ULNS and I have 10 fish which I feed pretty heavily. I use RO/DI water for top off and water changes, and am using Reef Crystals salt.

If it's not the alkalinity, then I have no clue what I'm doing wrong, because my tank is set up the exact same way as it was previously. Most of my equipment is listed in my signature.

Any thoughts?

Thanks!

 

[skinny sam]

It looks to me like you solved the problem on your own. That has happened to me when I had a test kit that was giving me the wrong reading and the corals did the exact same as yours. Just remember don't raise the ALK to much to quickly or you could make the problem even worst. Slowly raise your alk back up over the course of a week or so and test your new saltwater and buffer it if needed when you do your water changes. Hope your corals come back to their former colors.:thumbsup:

 

[mike_cmu04]

It is likely the alk get that fixed and the sps should come back.

 

[jdstank]

I use 2 test kits, one every week and the other every other week just to make sure the kits aren't going bad on me and avoid problems like this. One kit (the weekly used one) is strips which are replaced every 2 months so the chance of them going bad is much less compared to the full blown test which I've had reagents go bad in the past because they last so long.

If alk continues to be a problem you might want to try dosing a bit with a buffer to maintain alk.

 

[smtank]

Gotta bring up that mag level to at least 1350, and that will help stabilize the alk level.

 

[IFbettas]

Thanks for the advice everyone. I will start raising both the alk and mag up slowly and hopefully my corals will recover.

 

[Dustin1300]

Agreed on raising those two. I'd focus on the Mag first IMO as the lack of Mag will cause your alk/calcium to form precipitate.

 

[IFbettas]

I've raised up the alkalinity to 9dkh now and I'm still raising up the mag, but it's at 1300 currently. I forgot to mention that a few of my chalices are showing the same symptoms and that my frogspawn is receding from the base too. My zoas/palys are doing ok, and have excellent colors, but I'm not getting any growth at all on some of them. I have several clams in my tank too, which happen to be growing really well. I'm wondering if there might be more to my problem than just the alkalinity.

On the other hand, my green slimer which stopped growing entirely a couple months ago has now sent out two growth tips. Maybe the slimer is the fastest to recover, and the problem is now fixed?

 

[smoyer]

all good advice. I have moved my tank more often than I would like to admit and every time its a lot of testing and adjustments. It just knocks the tank out of whack and its seem to go thru mini cycles before it stablizes. Its normal to have growth slowed down you just stressed them out but if you keep your water chemistry up they should recover.