Using a canister filter instead of a submersible return pump

[peterp63]

I'm thinking about using a high capacity canister filter, like an FX5, as a return pump from my wet/dry filter sump.  The thought was that the oxygenated water would flow across the media in the FX5 making for some really good biological filtration.  Now, this is after the water has already been treated through the trickle system over some bio-balls.  Is this overkill?  Should I just buy a submersible pump like everyone else?  Is there enough head pressure to start up a canister filter being that they will be at the same level?

Anything will help!  Thanks in advance!!!

[CichlidFan]

Re: Using a canister filter instead of a submersible return

I understand your thought process here, and it sounds good in theory, but I have to believe it is a bit over the top, as far as making something simple kinda complicated.

It would be interesting to see this plan of your put into action and see how you rig up the FX5 and just how effective the extra measures would render the entire process.

Good Luck with it, if you should persue this endeavour.

CF

[eklikewhoa]

Re: Using a canister filter instead of a submersible return

Eventually the canister will clog up and either stop flow through the wet/dry or flood your house.

[peterp63]

Re: Using a canister filter instead of a submersible return

Thanks, CF.  My goal is to make my setup as maintenance free as possible with a bunch of Lake Tang fish (and I mean a bunch!).  I am in the process of setting up my new 210 that I recently purchased.  It came with an Ehiem Pro II 2028 that I plan on using to discharge through a reverse flow UGF.  This will utilize the gravel bed's bio and hopefully eliminate the need to clean the gravel.  Also, I have a large capacity sump that I would like to connect a plant refugium to.  This is where the FX5 would return the water back to the tank via a spray bar.  The more filtration the better, but I don't want to be doing anything that's not worthwhile...

[Zulaab]

Re: Using a canister filter instead of a submersible return

Personally I would run the two as separate.  If you have a failure of one the other one is running.  Another thing is what size tank are we talking about, and more important what size wet/dry

Here is why I am asking.   If you have a large tank, the FX5 might simply not be enough pump.  It only pushes with media installed 600gph (925 without any media in it)  On a large tank you are going to want to separate the two just to get enough turn over.

[peterp63]

Re: Using a canister filter instead of a submersible return

If the canister clogs up it will begin to impede the flow at which time I'll clean it just like any other canister filter... how would it flood the house, ek?  I'll be using an overflow box - what goes in must come out  ????

[eklikewhoa]

Re: Using a canister filter instead of a submersible return

If your water levels aren't spot on when that filter clogs one or the other will overflow.....also the canister is not gonna be able to push the wet/dry to it's full potential.

Then you say you want to stock the tank heavily....having both working separately would give you a higher turnover rate which would mean less stagnant/stale water.

[Hanson77]

Re: Using a canister filter instead of a submersible return

On your theory of what goes in must come out....  Just like EK said, your levels must be spot or your overflow will do just that....overflow!!!  If you plan to run the wet/dry in conjunction with the Eheim, just spend the money for a return pump like it is designed.  The return pump will cost about half as much as the second canister would and will give you considerably more flow in the end which is ultimately what you want.

[peterp63]

Re: Using a canister filter instead of a submersible return

My objective with the sump is to have the correct amount of water so that in the event of a power failure or equipment failure nothing will overflow.  Isn't this one of the main points for this type of filtration?  

And you're probably right... I should just buy a return pump as a secondary return from the sump to add more flow.  

Guys, I'm still having a hard time understanding how anything will overflow.  Can you please explain?  From what I can see, if my overflow or associated piping became plugged up then the tank could overflow.... how else????

[Hanson77]

Re: Using a canister filter instead of a submersible return

The issue is the rate at which your drain piping to the wet dry may exceed the rate at which your canister pump can get it back to the main tank.  This would then cause your overflow box to overflow because what is going in won't match what is going out.  This happens in the canister filters because either the media if full of garbage or the piping accumulates debris on the sides thus constricting the flow.  

As far as having issues with power failure overflowing one or the other can be addressed in a few different ways.  But they all depend on how the water is pulled from the tank to the wet dry.

[peterp63]

Re: Using a canister filter instead of a submersible return

How is the box going to overflow onto the ground??  The constraint is the amount of flow that the canister filter can pump back into the tank.  This controls the amount of circulating water..... With a decreasing amount of flow there will simply be less water circulating in the system.  The overflow box should not have a problem dumping water down into the sump.  I'm still confused guys.  Ek, can you help?

[CichlidFan]

Re: Using a canister filter instead of a submersible return

What they are referring to is the sump. When the water comes down from the overflow boxes on the back of the tank, the water is held in the "sump" portion of the wet dry and from there the return line of your cannister would take the water from the sump and push it back up into the tank.

They are saying, that if the FX5 or whatever cannister you used to return the water to the tank, if that filter got clogged, the filters' capacity to return water to the tank would deminish and the sump would then begin to fill...and eventually overflow onto your floor.

Keep in mind, the water will continue to flow into the sump, regardless of the rate of water your return pump is pushing.

Hope that helps.

CF

[peterp63]

Re: Using a canister filter instead of a submersible return

I think I understand how it works, but what everyone is saying doesn't make sense to me  :?

This is a closed system.  If you aren't pumping water up into the main tank then where is all of this excess water coming from.  How is it different from a power outage?  Basically, the way I see it is you pump water into the main tank and it overflows back into the sump.  If you slowed the flow of water, or even shut it off, the circulation would slow down or cease altogether.  The rate of water flowing into the tank should equal the rate of water flowing down into the sump; therefore, you should never have any spillage provided there is adequate room in the sump for the water in the pipes/tubes going to/from the tank because obviously gravity will force it back down into the sump.  

?????

[CichlidFan]

Re: Using a canister filter instead of a submersible return

No.....it's not closed, the sump is open.  The wet dry is fed by gravity, not by the FX5.

CF

[Zulaab]

Re: Using a canister filter instead of a submersible return

I am going to have to agree with Peter here..  the way the water comes into the overflow is because the water is high enough to flow in there.  If water does not come back into the tank because of a slower and slower return (until the pump ceases from not being able to push any water because the insides have become mud) there isnt any water returning to the tank to allow the overflow to drain out.  Ie this would be like when there is a power failure and it stops working.

I like his idea until the thought came.. how is the FX5 going to get feed water ?  It will NOT suck it out of the tank.. it uses gravity to suck it out of the tank just like the overflow box does it.

So the sump would need to be 100% over the canister which really means that you have some interesting construction going on under your tank.

To me is becoming impractical at this point to do this, unless you really want to have a 4-5 ft high stand.