Corals Dying

Do you know for sure that your hydrometer/refractometer is reading correctly and doesn't need to be recalibrated?

What kind of light?
What are your levels at?
How old is the tank?

The tank is four months old and is the Red Sea Max S-500. I switched from the Red Sea Max 250 to this new one. I've been in the hobby for several years and haven't seen any my corals die in such a short time. It has the 10 T5s and my hydrometer is only a few months old. All of the fish are doing well and I did a 25% water change two weeks ago. I have a UV sterilizer on the tank. A month ago, I battled Ich in the tank, but no signs of it in the past few weeks. I used the Fish Vet Ich medicine and everything seemed okay when using it. Now, after the last water change seems to be when the problem started occurring. 

Edited by Boston - March 29 2014 at 9:37pm

Maybe copper got into your system? Or as mark said a cleaner or something maybe in the bucket you ised

But maybe your carbon might have had some... have heard of a few batches that have had copper

I shut my heater off last week and my tank seems to maintain itself between 80-82 with it off. I will do a water change tomorrow and get my parameters back up to where they belong. Thanks for all of the help!

Boston wrote: hydrometer is only a few months old.

Unfortunately that does not give us any indication of its accuracy. New Hydrometers need to be checked/calibrated against a known salinity.

If turning off (unplugging?)the heater resulted in temperatures at 80-82, what was the afternoon temperature with the heater on and for how long was it that way?

I agree that temp is too high while every other parameter is too low. Several variables can combine to cause problems that would not have happened if only one variable went off. After a few months with these levels at or weekly falling to those values, it wouldn't take much of a single variable change like a short rise over 82 degrees to start the domino effect of corals passing away. As they die the N pollution rises, giving way to further stress and death by increased Ammonia and Nitrate. Unfortunately, without more details, all we can offer is conjecture. A pic of the tank may help.

Here is my opinion about these parameters:
Salinity is best at 1.024-1.026
Temperature is best, and safest, at 75-78 but can be anywhere between 70-80 without any problems
Alk should be kept at 8-12 dKH, preferably close to 10
Ca should be kept at 350-500, preferably close to 450
Mg 1200-1400
Daytime pH is okay between 8.0 and 8.4
Nighttime pH is best if kept above 7.80

As I am writing this, some things come to mind. Just throwing out possibilities to see where they land:
- pH problems? What is the water flow in this tank and in what direction or was there a power outage?
- Any new product is suspect, even if it is reef safe.
- Any change in procedure is suspect.
- Did the coral start dieing all at once or was it a cascade of one type and then another?
- I've seen medications work differently in different tanks and frankly I don't trust a medication that claims to kill one invertebrate yet causes no harm to other invertebrates. (Garlic Oil works very well for me. It is a natural Ich inhibitor.)
- If things went south after a water change then I would wonder if something got into the bucket when I wasn't looking.
- Was it a completely new salt mix? Problems with not gradually acclimating to a new salt mix have caused coral deaths.

My 2 cents.
Aloha,
Mark


Edited by Mark Peterson - March 30 2014 at 11:38pm

phys wrote: Check your thermometer.. it could be broken

Yes, that's a simple first test and that high of a temp without supplemental heating seems strange unless you have a lot of metal halide lighting.

Good call Paul.

If you don't have a fan on your sump you could add one. Cheaper than a chiller.