Coralline Issue....What am I missing?

[WillKatt]

This!!! Your mag is low most likely and lights are to bright... I can only grow coralline in shaded areas myself..

+1
Also you can get excellent Coralline growth with LED however I have found that even relatively small adjustments in the LED intensity can bleach the coralline really bad, stunt its growth and even after its been adjusted and all parameters are correct it takes awhile to start coming back.

This exact thing happened when iI switch from AI to Radion. All my parameters are spot on and very stable. Coral growth is excellent but just now after ~3 months has my coralline started to come back.

Did you make any changes with the lighting recently? Raise or lower the fixture, adjust photo period or intensity? If everything else is stable and you have good growth everywhere else just be patient it should come around.

 

[tcreeftank]

I went to my LFS last night and had the water tested to get a second opinion. Their results were almost exact to the ones I had taken except for one thing. The magnesium level as tested by them is closer to 1600!?!?! Now I am really confused as I had assumed that my mag level was on the lower side for the last 30-45 days or so.

I have started to lower the light level slowly. Will do about 3-5% per week until we get to a level about 25-30% lower than where we were before and see what happens.

I am going to do a large water change this weekend as well and try to test every day next week just to make sure everything is still in line.

 

[Chameleon]

ULNS can cause slowed coralline growth. Did you do anything like start carbon dosing or put in a pellet reactor of GFO that may substantially lower nutrients. Just a thought

 

[tcreeftank]

I have been running carbon and GFO since day one on this tank. Can't think of anything that might have lowered nutrients in the last month or so.