Small water change Killed my Fishes..

[janey]

I have a 30gal reef with lps and its been up and running for 2 years with no problem.
I did a water change last nite about 3 gallons worth. The water was 78 before i empty out the water i shut off all power. but left the 1 pump running for circulation. and i say it took me about an hour to clean out the carbon reactor and a small mechanical filter .
The temp i think was like 75 i poured back in some water which was cold, and put down the temp too 73 a I turned on the power especially the heater.

Then i noticed 3 of my fish ( clown , yellow tang and coral beauty) started to look bad hanging low and on there side. the other 2 clown and small yellow tang were acting wired too.
My 2 invertebrate ( blennys ) and 3 shrimps are fine no effect.

As the temp started to rise , i did a water test sal was a little high 1.28, nirate low , phospate low. alk was a little low 7.8.

I'm thinking maybe i have a short when i powered back the heater or skimmer. I did put my finger and no shock. LOlL . But what the HECK Happen?

? Later on i lost the other2 fish . All fish dead except the Blennys and shrimps..

 

[janey]

I also did water change about half a gallon same water on my pico which has to clowns and they are fine....

 

[jaa1456]

Why did you turn everything off? I don't get that part.

 

[xxxAngeloxxx]

Whats are your ammonia level at and pH too.

 

[B.BASH]

2 degree temp drop and spike in salinity in a short time is my guess

 

[janey]

i turn off the power cause when i siphon the water levels go down
and evrything is the back and the heater can crack and mechanical filter runs dry.

 

[janey]

I just found another fish dead , a blenny. he was fine this afternoon
got 1 more left and he looks fine and eating ???

 

[thirty5]

Lets start with what kind of water? RO? Tap?

 

[Dre]

It's almost impossible for someone to give a diognosis on your mishap. Some key points are also missing. How long did the salt mix before using? You mentioned carbon, did you replace it with new media? When was the last time you replace it? You probably released some nasty stuff back in the tank or you killed too much of the beneficial bacteria from the mechanical filter while cleaning it. I don't know, i hate these kind of threads..

 

[janey]

Ro water , Salt been mixing for about 2 weeks , I added new carbon . Now the carbon has been sitting in a bag for 2 years . Can that go bad ??? Oh No now i remember can it be the carbon i didn't rinse it. But i remeber when i plugged it in , i had some of the out put go into a bucket like 16oz of it.

 

[Dre]

I'm not saying carbon is the cause but i know if carbon is not used correctly and sometimes correctly can be problematic..

 

[JimmyR1rider]

Have you checked for any rusty metal parts? Maybe screws in your pump or a hose clamp that rusted?

 

[jaa1456]

Do not use carbon that is that old, even sealed it will absorb moisture. Who knows what is in that moisture and let alone 2 years worth of it. As for unplugging everything, make sure you only need to unplug the minimal amount needed. I can't see why or that many things needed to be unplugged. The heater should be able to run at all times, so look into a better placement for it. I always use carbon within 6 months, after that it gets tossed, even a half bottle. It could have sit in the store for a year, you never know. Maybe something got into your salt mix during the 2 weeks.

 

[janey]

I was thinking the same thing maybe a something fell in it while i was cleaning it.
But weird , i did another small water change like a gallon with fresh salt mix / Ro/Di 0 ppm and same temp as tank 78. I unplug the skimmer and heater . I check the heater and it looks fine . when i plug back in the skimmer and heater . 1 of the 2 blenny died.
Gonna pull out the skimmer pump and inspect that .

 

[janey]

and i also turn off
and took down the carbon reactor.