Fishroom/Large Tank Heater Ideas?

[DIYSeattle]

I have multiple 250 gallon tanks in my basement. The water temp there stays at 68 to 71 degrees without any heat at all. I dont want to have 3 heaters of 350 watts plugged in to each tank.

I looked at the house hot water heater ideas and it seems to be great if you wanted all your tanks the same temperature. I will have an issue with it because we are going to be going to a tankless hot water heater in a short while so I dont see any reason to set up the hot water heater to heat my tanks.

I have not seen much at all about a tankless water heater running large tanks. Would running a controller and a pump on a dedicated tankless electrical waterheater be a crazy idea? My house is set up for gas and I could run gas as it is cheaper and the main heater for the h ouse will be natural gas. Overall Im not sure if a tankless water heater would work. It seems like Id be able to set up a Ranco controller to a pump so that when the temp gets low the pump cuts on and the hot water heater works until the Ranco turns the pump off. I would think that running the Tankless hot water heater in a closed loop would be better. I think it is possible to get a hot water heater with an extra water setup like for heating floors. I think Ive seen some iwth multiple water lines for closed loop. Id have to look into that a bit more.

Anyone have ideas or concerns about using a tankless water heater to heat their large aquariums or sumps or fishrooms? I cant heat the room by itself the way it is set up. Id like to hear your ideas.

 

[gandalfdgrey]

I am using a tankless water heater and have two sets of tanks with different temperatures. I have two solenoid valves connected to two thermostats, when activated, hot water will enter the heat exchangers - heating water until the desired temperature is reached - which results in the solenoid valve being shut off.

 

[DIYSeattle]

Thats a good idea. Instead of having two seperate systems. I was almost thinking that having an open loop directly might work if I can get a thermostst that is low enough or somehow modify the existing thermostat. I was thikning to build a heat exchanger but I am/was unsure if a tankless water heater would work.

I know gas is much cheaper to run but Im not sure if I can get a second tankless water heater mounted and setup. A freestanding electric tankless waterheater would go over better until the electric bill came. Perhaps just plumbing in and setting up a smaller tankless gas water heater for the tanks would work and run solenoids like you did.

Are you using a Ranco controller? How exactly are you running your system?

 

[DIYSeattle]

http://www.aquaticeco.com/subcategories/3038/Aqua-Logic-Heat-Exchanger-Packages

I was thiking to build something like this maybe but it looks like it would lose a lot of heat if I did this type instead of just making a loop in the bottom of the tanks. Id prefer to keep the tanks as clear as I can from tubes and monsterous apparati. This would require two pumps though, at least one for the TLWH and one for the exchanger.

 

[gandalfdgrey]

I am using two of these type of heat exchangers - used in ponds and swimming pools. The hot water inlet of the heat exchanger has a solenoid controlled by an electronic thermostat. These type of heat exchangers are pretty efficient.

 

[DIYSeattle]

Someone suggested to check into spa or small pool heaters. The are quite costy and use a lot of electricity to run. Im not so certain about that route.