Cannister as a return pump from 'fuge

I see what your saying. the intake would be the problem unless the fuge is set higher then the canister. i think that would be my only problem cause right now i'm using a can. filter which has about about 3.5' of hose for intake and return. it works pretty well. think that might fix it?

 

also, how much flow should be running through, say, a 20gal fuge?

 

ive actually tried this with my ehiem and found that the canister filter needs the momentum from the water flowing down from the over flow straight to the canister, the canister dint have enough balls the pump the water back up by its self to the main display with out the push of the water that was behind it, how ever if i plumbed the canister into the main tank (both in and out flows) it worksd fine (as it should)

 

Well that Drawing just shows a like like a siphon from the main tank to the sump you have to have some type of control there water seeks its own level either a internal overflow on a drilled tank or a Hang on overflow to feed the sump. Now a Cannister will work on the floor and push the water up as long as its primed and never stops pumping . Like a jet or summerged house water pump on a well they have to have a foot valve to hold the water in the lines while the pump is off but in salt water the foot/check valves are useless as they foul after a few weeks . So what you need to do is add a HOB overflow or drill the tank and then I'd simple use a power head like a Mag or RIO for the return and get away from cleaning a cannister .

 

Ok, how much flow would you suggest? 75gal main, 20gal fuge.

 

Rather large fuge for that size tank .. A 10 would be the Max I'd use and then about 7 to 10 GPH through the refugium. Through the sump about 300 GPH max

 

well i say that cause i have a 20 long here gathering dust.

 

Sorry Phorn I didn't mean to take over your thread and your idea, but i'm intrigued.

 

Look with a refugium its not always more is better less is often enough. A 75 gallon reef on average load will support or excrete enough waste to feed on average a 10 gallon max.
Lest say you have a natural farm where all the animal manure is used for natural fertilization of the plants and its been running for yrs lets say it a 50 acer set up with 20 horses and cows and and chickens , Now you get the 50 acres next to yours to farm and want to double the plant yield's .. Where you gong to get the fertilizer from ? You have to double the animal load or lessen the volume of plant growing area back to 50 acres.. Its your farm and your call. But in a average 75 gal reef a 10 is a little larger then what you really need . I have for yrs based mine on the 10 % rule if figured out dealing with the refugiums . I size the refugium as close to 10% of the main system its to support then I pass 10% of the total refugiums water volume through the refugium pr hr. a 10 gallon fuge needs about 10 GPH through it. This allows time for the solids to settle out to the bottom . After its a saltwater marsh/ swamp we are tying to emulate..

 

Gotcha, good analogy, thanks