Heater overheated, did it kill the bacteria too?

[sparkydave]

My heater failed, and raised the water to 105F before I realized all the fish were dead . I unplugged the heater and netted them out, but would it have killed the bacteria too? It was like that for less than a day. Just wondering if I can replace the heater and fish, or if I'll have to re-establish the bacteria.

 

[OrangeCones]

First off, I'm sorry to hear of your loss.

I am more acquainted with lower temperatures (for outdoor ponds) than high temperatures, and its effects on nitrifying bacteria. In doing a websearch, I found this link:

Nitrifying Bacteria Facts

It states that 120degrees will kill the bacteria.

To be safe, I would assume that the bacteria was at least harmed in this process and proceed slowly. Can you add fishfood or ammonia directly to the tank and monitor the levels of ammonia, nitrite and nitrate? If you see ammonia and nitrite zero 12 hrs after adding food or ammonia, and nitrate rising, then you'd know the bacteria is still alive and functioning.

You could also 'seed' the filter media from one of your other healthy aquariums.

 

[KcMopar]

I agree, its more then likely still occupied with bacteria but its just easier in the long run to test it for a few days and make sure it does not crash. If no ammonia shows up after a few days of adding a bit of food you should be Ok.

 

[skjl47]

Hello; What type and brand of heater, submerged or hang on side? Was it the preset type or the type with an adjustable thermostat?

 

[sparkydave]

I forget what brand it is, it may even be Petsmart's store brand. It's a 300 watt adjustable and submersible. I just remember I got it from Petsmart years ago, and it has a black plastic body. The tank is back to room temperature, so I'm just feeding it and I'll see what the levels look like.

 

[OrangeCones]

The tank is back to room temperature, so I'm just feeding it and I'll see what the levels look like.

This small delay will give you the right answer.

Even though they say they last a long time, I replaced my heaters (when I lived up north) every 3 years. Now that I live in Southern Texas, not sure what I'll do, as it's seldom cold enough for it to kick on.

 

[skjl47]

Hello ; 300 watts in a 48 gallon tank. Stuck on would heat up the water fairly fast. The heater may be repairable. I have had the contact points of heater thermostats build up a small deposit. (Much like the contact points used to do in a car's distributor.) A thin flat file to clear away the small projection and it can be back in service. This will depend on your being able to open up the heater. I have not had a newer heater with digital controls apart so cannot comment on them. You may no longer trust this heater.

I have come to like two smaller heaters on a decent sized tank. That way if one fails it is less likely to overheat or allow the tank to be too cool.