Tank Filtration: overflow using canister?

[thecoolguy]

ok, so the 450gal is in the works - and it comes with a internal overflow, which im not too happy about, but can live with

i am planning on using the overflow box as a prefilter to the 3 fx5's i plan on using to filter the tank....

so without any sump vs canister debates - as i have made/used sumps in the past, is there any problem simply bottom plumbing the intakes to the canisters straight from the bottom of the overflow/tank?

not that you needed a picture....but something like this:

 

[Dan F]

ok, so the 450gal is in the works - and it comes with a internal overflow, which im not too happy about, but can live with

i am planning on using the overflow box as a prefilter to the 3 fx5's i plan on using to filter the tank....

so without any sump vs canister debates - as i have made/used sumps in the past, is there any problem simply bottom plumbing the intakes to the canisters straight from the bottom of the overflow/tank?

not that you needed a picture....but something like this:

You will need to keep your tank topped off at all times - if the water level drops below the overflow your canisters will run dry. Other than that I don't see a problem.

 

[aaronb]

Well the fx5 works on a syphon not gravity fed. I have seen canisters connected to drilled tanks without overflows that seemed to work fine. The problem you run into is sucking in air bubbles. I think if you connected them to the holes and then filled the overflow at least half full of water it might work. You shouldn't have the trouble of having enough water come over the overflow as long as you keep up on replacing evaporated water.

 

[thecoolguy]

great point - didn't think about the air bubbles...which isn't necessarily too bad a thing if its not excessive, as bb thrive on more o2 no? haha....

so yeah, i guess as long as i fill the tank to a point where there is a very abundant amount of water, enough where the overflow is always partially filled, i should be good....

this is all because i don't want to run a sump....haha

 

[Dan F]

great point - didn't think about the air bubbles...which isn't necessarily too bad a thing if its not excessive, as bb thrive on more o2 no? haha....

so yeah, i guess as long as i fill the tank to a point where there is a very abundant amount of water, enough where the overflow is always partially filled, i should be good....

this is all because i don't want to run a sump....haha

You will probably want to keep the overflows all the way full - the difference between partially full and running dry is only a few gallons at best, which can evaporate pretty quickly out of a 450 gallon tank.

 

[thecoolguy]

yeah....the more i think of it.....i will be removing the internal overflow and drilling some holes on the top to plumb up the fx5s

 

[aaronb]

Yeah I'd just fill it 90 percent full that way you wouldn't have to worry at all about too much water evaporating. You can also just drill holes in the overflow in random places so it fills from a lower point. I'd just keep and use them the way they are though. That way if you have a leaky bulkhead someday you won't have to drain the tank. Just lower the water level below the overflow and drain the overflow and fix it.

 

[maxxxx]

You will probably want to keep the overflows all the way full - the difference between partially full and running dry is only a few gallons at best, which can evaporate pretty quickly out of a 450 gallon tank.

Oddly enough, I have been running fx5 canister through a drilled tank for some time with great success.

n.b. My first shot at this rig; the pics are little old and I've added some improvements since; but you get the idea

 

[Dan F]

Oddly enough, I have been running fx5 canister through a drilled tank for some time with great success.

n.b. My first shot at this rig; the pics are little old and I've added some improvements since; but you get the idea

Of course it can work if done right.

The O.P. is talking about using an internal overflow, not just a bulkhead with a strainer like you are running. With your layout you don't have to worry about sucking air until the water level drops considerably.

 

[thecoolguy]

ok, no more debate.....

have decided to use the overflow as a mounting point for the main aquascaping...

might even drill out a small hole towards the bottom and run a low gph pump, and put some plants in there....haha