450 Gallon Tank Overheating

We have a 450-gallon aquarium that is 42 inches deep, 96 inches long 24 inches wide. We set it up with the fluval filtration system, automatic water changes, lighting, and air pumps. We also have a Neptune Apex system to monitor the tank. Because we live in southern California it is hot, but we keep the air conditioning on in the house at around 78. Our water temp. has been around 80 degrees so we turned the heater off a week ago. Last night the aquarium temperature spiked up to 90 degrees. We are installing cabinets above the tank and 2 out of 3 cabinets were installed. We have two air pumps-one for deep water 150 and another whisper pump that was not made for deep water, which seemed hot and made lots of noise. I unplugged the whisper pump in case that was the culprit and ordered a deep water 300. I have been putting frozen water bottles in the tank to cool it down. It is now 86 degrees and dropping. Could the cabinets above the tank be the cause of the temperature spike? Could the airpump that was not designed for deep water be the cause? We have Lake MalawI Mbuna African Cicchlids in the tank.

 

Welcome to FishLore!

I suppose both things could be adding to the heat. Was the tank temp lower before you started installing the cabinets?

 

Here are the photo of the aquarium before upper cabinets and after the two were added.

Welcome to FishLore!

I suppose both things could be adding to the heat. Was the tank temp lower before you started installing the cabinets?

It was 80 degrees before with no heater on. Please see photo of tank with and without the cabinets installed. I'm trying to find out if you are not supposed to put cabinets over an aquarium in general.

 

Evaporative cooling is pretty effective with that large of a surface area and your new cabinets may be blocking that. Maybe you can put a minI clip on fan somewhere to get airflow across the top of the tank?

 

So placing the cabinets over your tank is not necessarily going to have an appreciable effect on temperature. Evaporative cooling in this case is negligible since the diffrence in temperature internal to the system (tank) and the exterior heat sink (room) is insufficient to actually create thermal driving head. The problem is you have a lot of water volume and it all heated up to 86 degrees. Given the specific heat capacity of water it will take roughly 30 hours for the temperature to drop to 80 degrees with no outside influence. Placing the frozen water bottles in the tank is a good start however conduction will overcome the temperature and you won't have sufficient thermal mixing without a circulation pump (powerhead) what you need is a chiller and something to add some turbulent flow to actually mix the temperature layers to achieve a lower normal. Chillers can be made or bought.

Hope that helps.

 

I have seen tanks with cabinets on top, and I've seen built in tanks, but I do not know if people who have them have tank temp problems. You could always buy an aquarium chiller, though I believe they are a bit pricey.

By the way...putting cabinets in the hard way. I definitely would have started in the corner and worked my way out.

 

I have seen tanks with cabinets on top, and I've seen built in tanks, but I do not know if people who have them have tank temp problems. You could always buy an aquarium chiller, though I believe they are a bit pricey.

By the way...putting cabinets in the hard way. I definitely would have started in the corner and worked my way out.

Yeah never start in the middle. Tile yes cabinets no.

Building a chiller is very easy just need the parts. I built one for a buddy of mine based off my PC liquid cooling system.

 

Evaporative cooling is pretty effective with that large of a surface area and your new cabinets may be blocking that. Maybe you can put a minI clip on fan somewhere to get airflow across the top of the tank?

Thank you! A fan is a good idea.

Building a chiller is very easy just need the parts. I built one for a buddy of mine based off my PC liquid cooling system.

Thank you! The wrong air pump seems to be the culprit. It was not for deep water the heat was caused by it overworking. The last cabinet was not added because we wanted to make sure that was not causing the overheating. It fits with no problem!

Yeah never start in the middle. Tile yes cabinets no.

Thank you for your advice. I'll let my husband know. He is a General Contractor and builds houses for a living. He didn't put the last cabinet in because we wanted to make sure that wasn't causing the overheating.

So placing the cabinets over your tank is not necessarily going to have an appreciable effect on temperature. Evaporative cooling in this case is negligible since the diffrence in temperature internal to the system (tank) and the exterior heat sink (room) is insufficient to actually create thermal driving head. The problem is you have a lot of water volume and it all heated up to 86 degrees. Given the specific heat capacity of water it will take roughly 30 hours for the temperature to drop to 80 degrees with no outside influence. Placing the frozen water bottles in the tank is a good start however conduction will overcome the temperature and you won't have sufficient thermal mixing without a circulation pump (powerhead) what you need is a chiller and something to add some turbulent flow to actually mix the temperature layers to achieve a lower normal. Chillers can be made or bought.

Hope that helps.

Thank you for your thoughtful reply and for taking the time to think this through. The temperature is dropping. It has gone from 90 to 84.5 degrees and is still dropping. Question: We have 2 fluvals that are filtering and air pumps and automatic water changes twice a day. With this much water movement, is it still necessary to do more to circulate the water? It seems that the one air pump that was not built for deep water is the thing that spiked the temperature. As soon as it was unplugged the temperature began to drop.

 

Thank you! A fan is a good idea.


Thank you! The wrong air pump seems to be the culprit. It was not for deep water the heat was caused by it overworking. The last cabinet was not added because we wanted to make sure that was not causing the overheating. It fits with no problem!


Thank you for your advice. I'll let my husband know. He is a General Contractor and builds houses for a living. He didn't put the last cabinet in because we wanted to make sure that wasn't causing the overheating.




Thank you for your thoughtful reply and for taking the time to think this through. The temperature is dropping. It has gone from 90 to 84.5 degrees and is still dropping. Question: We have 2 fluvals that are filtering and air pumps and automatic water changes twice a day. With this much water movement, is it still necessary to do more to circulate the water? It seems that the one air pump that was not built for deep water is the thing that spiked the temperature. As soon as it was unplugged the temperature began to drop.

So the air lines will create a turbulence channel in the water column as well as causing surface agitation. The air stone effect creates a localized low pressure region which will draw water towards it. So that will cause circulation and eventually you will even out the temperature.

 

Thanks so much!