Canister filter can filter two tanks?

[MiamiCuse]

I have one 29 gallon and two 10 gallon tanks, I might go for a 60 gallon soon but not sure when.

I generally do not like the HOB and if I add a tank, get rid of a tank you have to factor in the filters.

I would rather get a large canister filter that can do 100 gallons or more, and have it work for all my tanks, if possible.

Is it possible to filter three tanks with one single canister?

Can I plumb three PVC lines from three tanks into the inlet and split the outlet into three?

I assume since the three tanks need different output volume (or else the smaller tanks may overflow) I could install a gate valve on each outlet to calibrate the volume of the output to each tank to match the intake?

[Bodhi]

It might be tricky to get it balanced, but if you have the time and know how for the plumbing, I'd go for it. Basically it's what most chain stores like Petsmart do, except they use a large sump filter.

[terrapin24h]

It might be tricky to get it balanced, but if you have the time and know how for the plumbing, I'd go for it. Basically it's what most chain stores like Petsmart do, except they use a large sump filter.

Indeed, and just like in big pet stores, if a parasite, pest, or disease broke out in one tank it would soon spread to all. As would any water quality issues. This would also make your tanks pretty inflexible...They'd all have to be the same temp, same hardness, etc. Also, if you ever had to treat a tank for algae, disease, etc, you would need to dose enough to cover all 3 tanks. You'd get butt kicking gas exchange though. Personally, i see more drawbacks than gains.

--chris

[MiamiCuse]

I think if I install the gate valves on both the inlet line (one from each tank) and same for outlet. I should be able to balance them by setting the valve to the same flow. If it's drawing whatever volume per second on inlet it must expel the same volume per second as long as it's the same diameter going in and out of the tank. I believe. I will double check my old fluid mechanics books.

As far as treatment of individual tank, I do have an extra HOB filter available if needed, I can always cut one line off and isolate one tank if special treatment is warranted.

Yes disease will spread.

It's a big gain in terms of flexibility, I believe.

[james481]

The only way I would do this is if the tanks are draining through drilled overflows into a sump from which the canister can draw the water. If you have three inputs and three outputs from a single pump (filter) and you're trying to balance them with gate valves, you're never going to get it exactly right. You'll perpetually be fiddling with your valves trying to get your flow rates exactly right. Worst case scenario is you overflow one of your tanks all over the place, while draining the other tank to the input. I would rely on gravity (hasn't failed yet) and over sized drilled overflows. Then, your only worry is getting the amount of water going into each tank where you want it. Worst case scenario is your 10 gallon tanks gets too much flow and your 29 gets too little. I'm actually building almost the same thing right now, but running two tanks (29G and 15G) off of a 15G sump (no canister filter involved, but I am only going to use a single pump for both tanks).

[Bodhi]

Have you considered a flow-through system? I personally believe these are superior provided you have a way of filtering your tap water. Essentially your plumbing would be no more difficult than what you propose, but you'd be skipping the expense of the canister entirely. If I lived in a house it's what I'd do since my water is naturally chlorine free and soft, which is good for the species I like to keep. Another advantage; never having to do a water change again! :)

[W_Oz]

I would agree with the Sump approach as being more effective in this regard, however I don't agree that you'll need to drill the tanks to do it. While drilling might be the "easy" solution, I hate putting holes in glass aquariums. Anyway, if you were to build overflows for each of the individual tanks, then have those overflows feed a sump, doesn't have to be anything fancy or more than say a 5 gallon bucket or 10 gallon aquarium/tub, then split your return line through a manifold to go to each of the tanks. Then either drill anti siphon holes in the return hardware at the tanks to keep the system from sucking water back through the canister to the sump if the power goes out or install check valves.

OOOOOOOOR you could just nix the canister and build a wet/dry sump filter. Which are pretty easy to build from commonly available plastic storage containers/tubs and the overflows can be made of PVC. Your biggest expense at that point would be buying the return pump.