need help, will 75deg water bleach sps or is it something else

[jarrett shark]

1st not sure whats killing my sps but I added 150gals(frag tank) to my set up a week ago not relize that i need to add a heater, well it was real cold in NY this week and my apex graph shows tank went down to 75deg for 2-4 hrs of everday this week at night. I see some sps bleaching at base and trying to see the problem

2nd
i have 3 MH and I upgraded 2 of them from 250w to 400w 2 weeks ago. I did run my light for less hours to break them in but its all in the same time.

3rd

my calcuim reactor has been acting up in the past month, so 2 weeks ago i changed media and could not level out my levels to get perfect so today i read the dkh 12.8 so i shut of reactor until i see levels get back to 10dkh
i think its the buble rate was to high


It might be all three but before i change back to 250w bulbs and start doing water changes every other day i thought maybe get your imput:wavehand:

 

[seminolecpa]

I highly doubt it is the temp. I let my sps get to 74 all the time with no problems at all and know others that let their tanks get as low as 70-72. 74-81 is pretty much the ideal range I shoot for.

I would bet the lighting upgrade from 250W to 400W has at least something to do with your issue. Just cutting the photoperiod down isn't really enough as the intensity change is still there. Ideally if you change bulbs to a higher wattage or par you should do it gradually. I personally have used mesh screens that I remove over a period of weeks to let my corals acclimate.

 

[jarrett shark]

is it to late to put screens over tank or what is done is done

 

[jarrett shark]

i also just ordered new 20k raduims and not sure what this will do

 

[tozzi]

not the temp. My tanks been at 72 for some time before and it was all ok

 

[Dustin1300]

The screens cannot hurt anything IMO.