bleaching SPS

[mchammer]

I've had my 120 gallon tank up and running for a 1 1/2 years and beside a few ups and downs (due to my messing with the tank ). Things have been going well even some of my earlier corals which almost died due to ALK swings were coming back but just this week most of my corals started to bleach from the top down and I don't know why. The only thing I've done is raise my lights to 11" off the water surface from 8". I did have a mishap with my ATO system and it dumped 10 gallons of RO/DI water into my system. The SG went from 1.025 down to 1.023, I'm not sure if this would have an effect on my SPS. If some one could give me some help I would appreciate it.

Thank You

 

[mchammer]

bump

 

[crissie]

How quickly id you raise the SG levels after they dropped?

 

[mchammer]

I unplugged my ATO and when ever I needed make up water I would fill with fresh saltwater. About a week until it got back to 1.025 SG.

 

[shih87]

May I ask your ALK swings happen over two months or within two months?

 

[mchammer]

it was a while ago I was having problems with my ALK. I was doing water readings and then I would adjust my ALK and then it would be too high and then too low. I finale just let the tank be and did water changes every two weeks and things seem to get better. Now I'm not sure whats going on. Corals were growing and looking good and then the past week or so things went south.