View Full Version : Minor Tank Disaster: Heater Blew Up

08-09-2014, 01:19 AM
Last night I noticed a very strange smell near my aquarium. I thought it was coming from a heating vent located near the aquarium so didn't think too much about it. As time wore on the smell became more and more pronounced so I did the sniff test and noticed it was coming from the aquarium. I thought that things looked a little darker but couldn't find the source of the problem. I put my hand in the sump to check something and that's when I noticed it had cooled off significantly. When I pulled my hand out it had a bunch of black muck on it and I noticed bubbles coming from the heater.

Heater blew. Temp was down to about 74 degrees. It's a FOWLR tank right now with some chromis, a pair of clowns, a coral beauty, and a pajama cardinalfish.
Also had a decent CUC consisting of some blue and red legged hermit crabs, astrea snails, some other snails, and three peppermint shrimp.

I was able to get a new heater in there today and it's slowly coming back up to temp. I pulled a couple of dead astrea snails from the tank. The fish seem OK. Probably not very happy with the cold, though. I've seen one live peppermint shrimp but the others are nowhere to be found. The hermit crabs and other snails can't be found right now.

I was unable to do a water change right away because I didn't have any new water mixed (LESSON LEARNED) so that's mixing and heating as we speak and I'm going to do about a 40% water change tomorrow.

The crappy thing is that everything has this light coating of black muck on it. It's very faint. But if I rub my finger across the glass just above the water line it looks like I've painted it with a black marker. It's very black. It's all over the rocks, all over everything. I have no idea what it is. Moreover I have no idea what else could have been in the heater that may hurt the aquarium in the short term. By far my greatest fear is losing the biological filter but so far so good. Still testing 0 for ammonia and 0.25 for nitrite. I think if there was going to be a serious problem there it would have already manifested itself.

I'm curious to know if anyone else has experienced something like this. Especially with the black muck that's all over everything. Any hints on how to clean it up? It's a 55g tank but I have a Tunze 6095 and a 6105 in there (throttled with a 7096 controller). I could turn them on full blast for a few minutes and see if that helps get some of the crap off the rocks. I'd love to hear any suggestions. Thanks.

08-09-2014, 03:38 AM
Was it a 200W Cobalt Neotherm? those have apparently been blowing up due to a manufacturing flaw.

08-09-2014, 03:53 AM
could you post a picture of this black stuff ? That would help.

74 degrees isn't that cold. I suspect the temperature dropped gradually so it probably didn't shock your fish. Last year my tank lost power for 24 hours and my temperature dropped to the mid 60s and I only lost 2 fish (but that was probably more due to lack of oxygenation).

08-09-2014, 03:20 PM
Thanks for the replies. This might be a non-issue. The tank is looking a lot better today. A lot of the black stuff that was on the rocks is gone. I'll wipe down the inside later and post a picture of the black stuff on the glass.

I guess the only thing I need to worry about is my CUC. They've disappeared. I suspect the hermit crabs buried themselves in the substrate. I hope I don't get a mass die-off of inverts.

08-09-2014, 04:56 PM
Clean up crews in general can be hit and miss. They (snails and hermits) can just up and die for various reasons. One reason being the lack of stuff to actually clean up (ie, food). Another reason is competition. It's a hard knock life being a snail or hermit crab scrounging for leftovers. I guess what I'm suggesting is that the die off of your CUC could be unrelated. Hang around the hobby long enough and you'll hear repeated frustrations of people having troubles keeping a clean up crew. In the end your tank will sustain whatever clean up crew it can. You can buy all the snails and hermits you want but your tank will only be able to sustain a certain population which may or may not match what you've actually purchased (usually not).

08-09-2014, 07:19 PM
That's good perspective kien. Thanks. I think I was probably a little heavy with CUC to begin with. So you're right, it might have been teetering on the brink to begin with and then this incident might have just pushed some over the edge. I am seeing some life with the crabs and shrimp so that's all positive.

Ya know this has been a great learning experience. Mother Nature has a way of taking care of some problems by herself. My protein skimmer has been working overtime and has pulled out all sorts of dark nastiness. I just did a big water change and in the process checked for black sludge. It was almost all gone. I wiped it down with a paper towel anyways but really the tank seems to have recovered well on its own.

And you can bet that now that I'm done with the water change I already have sea water mixing and am making more fresh RODI water to have on hand. :) That's probably the best lesson in all of this. You just never know when disaster might strike.