use a hangon filter for overflow???

[celtic_dude]

I have been considering getting an overflow and sump for my 29g fowlr tank. I have a whisper hang on filter that I was told I really don't need if I get a protein skimmer and set up the sump/refugium. So I was wondering if anyone has ever tried making an overflow with the hang on filter. Any Thoughts?

 

[theotheragentm]

If it's hanging on, it's going to be higher than the rim of the tank. How is that going to work if it's not closed off? Maybe someone else knows, but I don't think it'd work.

 

[artoledo]

I agree with agentm. Overflows work to prevent water from flowing over the rim of the tank. Overflows are placed in the tank not above. So the answer would be no. It will not work.

 

[celtic_dude]

Well I was thinking of using the built in pump in the filter to draw the water and balance it with an adjustable flow pump for the return

 

[artoledo]

It still wouldnt prevent an overflow.

 

[theotheragentm]

Using two pumps will eventually result in an overflow unless both tanks are oversized to handle the volume of the combined tanks, which would be a waste. Even with identical pumps, clogging will slow one down, resulting in an overflow in one of the tanks.

 

[celtic_dude]

So then the best solution is to have an over flow that relies on gravity and a pump to bring the water back to the tank?

 

[ezy33]

Yes, just make sure that the pump won't pump more than the overflow. If required use a valve on the output of the pump to lower the GPH.

 

[artoledo]

Yes, just make sure that the pump won't pump more than the overflow. If required use a valve on the output of the pump to lower the GPH.

Just be careful not to burn out the pump with the valve.

 

[jsoong]

I HAVE made an overflow with an old HOB filter (AC 70?) .... but that requires cutting the tank!

I cut off a 2"x8" piece off the top of my back pane of glass. This allows me to inset the the HOB into the back of the tank so it is lower than the water line (siliconed for water tightness). My return pump takes water from the sump into the tank, which overflows into the HOB, and is piped back down to the sump (by gravity only - no pump needed).

This overflow works like a conventional hang-on-back overflow, but with no need of siphons (and no risk of flood from siphon failure).

I use 1.5" pipe to connect the HOB to the sump, which allows me to build a compact Durso standpipe inside the HOB for noise control. It is small enough to not intrude into the space where the media normally sits, so I can use the existing media basket to hold a sponge prefilter.

My current setup handles 700 gph without problems. Looking at the "thickness" of the water flowing over the lip, I would guess that I can go to 1000 to 1500 before a flood.

This is my original post & pic: http://www.aquariumadvice.com/viewtopic.php?t=86032&highlight=