corals dying

[abraham]

AAAHHHH!!!! About half of the corals in my tank have started to die. My water tests great, no changes to any of my perameters. Other corals in my tank seem unaffected. also my clams are doing well. The only thing that has changed in the last three months or so was the addition of a sky watcher goby. I know that this is a bit vague, but I guess I need to be asked questions so I know the specific info need to help me. Please, anyone got some ideas???

 

[teevee]

What kinds of corals, what are the specs of your tank...

 

[abraham]

ok- the water temp. is 80 degress.
nitrate - 0
carb/alk - 7.2/2.57 this is the only change, was 10.2KH/3.66ALK 1 month ago.
ammonia <0.5
phosphate - 0
nitrite - 0
PH - 8.2
calcium - 485
The corals seem to be melting. I'm losing a frogspawn, and a couple of my SPS's that I'm not sure of the "make" and "model" ( I know, shame on me). I just don't remember what they are. The tanks been up and runnig for 14 months. I'm running a 58 gal tank with a 150 gallon refugium. a protien skimmer in the refug. my lighting is 2 - 400watt MH. I just replaced the bulbs in January,(I replaced them with the same type - 10,000k). I'm not running any carbon. I think that covers it. thanks again

 

[DougBak]

It *could* be the new lights... I've been reading a lot about MH lately, and a few of the bulb descriptions say something to the effect of "After the break-in period of 30 days they will emit the full spectrum of light".

Having not used them yet, I can't say this is definitely the case, but it makes sense that if the lighting has changed, your corals could react to that change.

I know you said you replaced with the same type (10000K) but are they from the same manufacturer? Different 10000K bulbs will put out slightly different spectrum and intensity of light.

You don't have any inhabitants in the system that put off toxins when stressed, do you?

 

[cdeakle]

ammonia <0.5

Needs to be 0

 

[Unarce]

420puff might be on to something. It would explain why the clams are doing well since they'll feed off of waste. It's possible that the ammonia has weakened some of the more sensitive corals, making them more susceptible to pathogens. Are you experiencing WBD or SDR (some type of RTN)? Could be a chain reaction.

 

[abraham]

I'm using a salifert test kit, the lowest reading that is available is less than 0.5 (<0.5). it won't tell me anything lower. the system has always been at this reading (since the cycle). The lights I'm using are ushio.

 

[jbpig]

Have you tried a LARGE water change?

 

[abraham]

Well, I may have figured out my problem! My heater is apparently going bad. I'm so use to the temp. being rock steady at 82 that i've gotten lacks on checking it. I noticed that even though my controller said 82, my tank was only at 72! Could this be my problem?
:? :roll: