rkpetersen
walked the sand with the crustaceans
When I got back into the hobby a couple years ago, I started out using two 200W Cobalt Neo-Therm heaters in my 100g system. I admired their 'unbreakable' and compact design. They worked flawlessly, maintaining the set temperature surprisingly tightly. Then, about 6 months later, I stumbled upon a number of reports of the plastic cases of these heaters spontaneously cracking open, and in some cases releasing toxic materials into the water and even the air above the water. Here's one such thread. Some of these stories are horrifying. I figured the risk was probably small, but even so, too catastrophic it it were to happen, so I removed the Neo-Therms and switched to EJs. Problem solved.
However, since the Neo-Therms were working perfectly fine, I put one of them into a seldom-used quarantine tank, where I set it to 78 degrees. Didn't think much about it after that. Put some fish through quarantine now and then. Then, about a month ago, with no other fish in the tank, a placekeeper sapphire damsel died. Hmm, no reason for that, well whatever.
Two days ago, I glanced at the running but otherwise empty tank and find the temp at 72 degrees. Heater display is lit and says that it's trying, but clearly no heat is being generated. Put my finger in the water gingerly; slight electrical current, that's new. Pulled the heater and yup, big crack down the side of the case:
It didn't see any obvious toxins in the water or smell anything in the air, but clearly something was starting to ooze out at the end. And, something did kill that damsel a month ago. If this had happened in one of my DTs, it probably would have tripped my GFCI eventually, but would that happen immediately, or after the case had been leaking god-knows-what for awhile?
Anyway, if you happen to have any of these in service, I'd replace them yesterday. I though the odds were low for it happening to me but this one cracked with relatively mild use. As I mentioned, this is the 200W model; some places, like BRS, don't offer this size anymore; I don't think it's a coincidence. The smaller sizes seem to be safe, more or less, and the 300W model is just two 150W heaters operating in tandem.
However, since the Neo-Therms were working perfectly fine, I put one of them into a seldom-used quarantine tank, where I set it to 78 degrees. Didn't think much about it after that. Put some fish through quarantine now and then. Then, about a month ago, with no other fish in the tank, a placekeeper sapphire damsel died. Hmm, no reason for that, well whatever.
Two days ago, I glanced at the running but otherwise empty tank and find the temp at 72 degrees. Heater display is lit and says that it's trying, but clearly no heat is being generated. Put my finger in the water gingerly; slight electrical current, that's new. Pulled the heater and yup, big crack down the side of the case:
It didn't see any obvious toxins in the water or smell anything in the air, but clearly something was starting to ooze out at the end. And, something did kill that damsel a month ago. If this had happened in one of my DTs, it probably would have tripped my GFCI eventually, but would that happen immediately, or after the case had been leaking god-knows-what for awhile?
Anyway, if you happen to have any of these in service, I'd replace them yesterday. I though the odds were low for it happening to me but this one cracked with relatively mild use. As I mentioned, this is the 200W model; some places, like BRS, don't offer this size anymore; I don't think it's a coincidence. The smaller sizes seem to be safe, more or less, and the 300W model is just two 150W heaters operating in tandem.
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