Running chiller through multiple aquariums

[StolleMan]

Hey all,

I was wondering if it was practical to try and run a chiller through 2 tanks. I was thinking of pumping water from 'Tank A' to 'Tank B'. Having the chiller inlet in 'Tank B' and the outlet in 'Tank A'.

If I could get the flows of both pumps to match up perfectly, could this work?

 

[callina]

I don´t know, if it will work, but if the chiller is big enough - why not?

But, if there is an illness in one these tanks, you´ll have to clean out both tanks.

 

[caleb]

I was thinking of pumping water from 'Tank A' to 'Tank B'. Having the chiller inlet in 'Tank B' and the outlet in 'Tank A'.

If tank A & B are at the same level, you could set up a siphon instead of the pump between the tanks (diagram attached). This would maintain the water at the same level in both tanks, without any need to try & match pump outputs.

 

[Jennewt]

I agree with Caleb - if the tanks are connected the way he shows, there is no need for a second pump. However, there is a "point of failure" in the setup. If the siphon tube ever gets clogged, one tank will overflow and the other will empty. I had this happen in a pond setup with two sub-ponds connected with a single water system like this. Fortunately, the results were not disastrous.

 

[StolleMan]

Would I get enough flow from a siphon to adequately spread the water for cooling? The only thing liable to block the pipe would be one of the axolotls... I don't see that happening.

My two aquariums are different sizes and filled to different heights unfortunately, both are sitting on cabinets, so raising the smaller one isn't really a viable option.

I did see a flaw in the pump system as well, should one of the pumps fail, or the flow rate be altered for any reason, then I will be left with an overfilling tank.

Maybe some sort of float valve cut off?

 

[SludgeMunkey]

I would use anti-siphon check valves in the in all the tubing and hoses. A push to connect PVC version is available at many DIY and hardware stores, also online from industrial supply houses. I just recently purchased a dozen 3/8 PVC push to connect check valves for 40 dollars(shipping included).

Another issue you may run into is tubing inside diameter versus flow rate. There is some math involved here, or you can use my preferred method of experimentation.

The biggest issue is chiller rated capacity and the TOTAL volume of water in the circuit. The more water volume you add to the circuit, the less cooling you will get. Additionally, you will experience less cooling the farther from the chiller and the base reservoir you get. Too much water and you will quickly burn out your chiller due to thermal overload.

 

[oceanblue]

You are getting into some quite complicated plumbing here and the more complicated the more problems.

I run two tanks together, a pump/filter one way and syphon return. The surface water levels are almost equal. Different tank sizes are no problem with a syphon system but different surface levels are.

I have both tanks filled to levels where syphon failure results in greatly disparate levels but not overflow or total drainage. The pump is positioned so it cannot totally empty its tank and the receiving tank has enough height above the usual fill line to take anything chucked into it without overflowing.

I linked my tanks because I had a tank which was slow to cycle and I needed to get stable biochemistry before a weeks holiday. I've kept the system going since for about two years. I've had two syphon blockages and a clogged filter effectively a pump failure, but no disasters!

 

[StolleMan]

Thanks for the help guys.

I shouldn't have any trouble assembling the system or exacting the flow rates. I am a landscaper and whilst new to aquariums, it all seems to be a similar science to residential irrigation.

A siphon setup would be easiest, but it's not really practical to have the water heights at the same level.

I'm thinking about creating a setup along the lines of the attached image. If I have the inlets high enough so as the water can never overfill either tank. In a worst case scenario I will be left with one damaged pump from sucking in air, a cost I can probably afford to wear should it occur. Obviously I will attempt to position the chiller in such a way as the distance that the 'cooled' water has to travel is at a minimum.

Any thoughts?

 

[Jennewt]

It looks awfully tricky to me. The flow rates of Pump A and Pump B would need to be perfectly matched. If not, you'll end up with Tank B overflowing and/or one of the pumps running dry. Are they the type of pump that can run dry without being damaged? Are you still thinking of some kind of float valve?

What is the current difference in height between the water surface of Tank A and the water surface of Tank B? It still seems to me that the engineering would be less complicated if you reworked the cabinetry and supports to put the two tanks on the same level.

 

[StolleMan]

Yeah, I think I'll go with a gravity fed overflow rather than the second pump, there seems to be little chance of error if I'm only running one pump.

 

[Jennewt]

Whichever way you decide to do it, please post photos when you are done!

 

[StolleMan]

I ended up drilling a hole in the side of the larger aquarium so that water can just gravity feed out of it.

The larger tank operates through the chiller as standard, but the smaller aquarium can pump water in to the larger, as the level rises the water can spill through the overflow and return to the smaller aquarium, theoretically keeping the water at a cooler temperature.

Using taps, I have made it possible to isolate the smaller tank from the larger for quarantine type scenarios.

I have also set up computer fans on top of them both to hopefully minimise the chiller run time.

It's hard for me to explain, I hope that made sense.

I'll post a photograph as soon as my partner gets home from work.

 

[StolleMan]

Well, here are the photos. The wires and pipes are going to need a bit of consolidating to get it looking a bit tidier, seems to be working pretty well at the moment.

Thanks everyone for your input.

(When I took the photos, the fans were both operating and spinning. They look as if they're not, my girlfriend's camera is pretty flash!)

 

[BBJ]

Damn, thats a pretty complex system you designed there hehe, very cool! Took me a while to wrap my head around that diagram! But it seems that there is no point of potential disaster, unless of course you spring a leak somewhere!
How is it working so far? Is it providing the cooling you desire?

Regards Bjorn

 

[StolleMan]

Working really well actually, couldn't be happier with the way it's keeping everything chilled. As an added unforseen bonus, when doing a water change, I need only to add water to one of the aquariums and the water level sorts itself out.