DIY small canister filter

I recently started a small canister filter project- my first DIY filter. This is meant for no larger than a 75 gallon tank. It is so far built from 2 1-gallon tupperware style containers. The water from the tank comes in at the top of each canister and flows down through the media into a collection chamber (made from the bottoms of plastic milk cartons) at the bottom of each canister. The water is then suctioned out through a length of pvc running through the center of each canister and either is pulled into the next canister or returns through the pump back to the tank.

The first canister is currently filled completely with filter floss scavenged from plain polyester quilt batting. The second canister will probably be filled with ceramic or live rock biomedia. I am still unsure as to where I should put activated carbon and whether it should be in a bag of its own. I am thinking it would be best to place the carbon in bags in the collection chamber of the first canister.

The tubing is 1/2 in. ID pvc in the canisters, 1/2 in. ID flex vinyl between canisters and pump, and 1/2 in. ID no-kink rubber hose from and back to tank. There are 1/2 in. pvc ball valves on the inlet and return rubber hoses.

Water will be siphoned out through a Rena Smartheater (it is a filter intake as well as a heater, so as to increase surface area, and flow-through as well as to decrease the number of visible 'outside items' in the tank). I am still unsure about whether to return the water to the tank via hose, powerhead, spraybar, or trickle canopy.

I ordered a Lifeguard Quiet One 1200 pump for this system (rated~ 296 gph).


Any suggestions? They would be greatly appreciated.

Sorry about the rotation on the pictures.

KaiserSousay;4959772; said:

Good luck.
My advise is test-test-and test again.
...Given prudent testing most all flaws will show up.

Click to expand...

Dan F;4959970; said:

What do you think the chances of the Tupperware lid withstanding 150 pounds of force? This doesn't even take into account pressure from the pump as the media clogs.

Click to expand...

Yeah. I just thought to test the system by closing a ball valve and breathing into it... the lids began leaking instantly around the edges and popped off around 6 psi. Then I tried to put the system under suction, again just with my lungs, and it leaked then too. It looks like I may need to band the lids on, silicone them shut, or just start over.

I have been thinking of trying to do this in a 5 gallon barrel with a lid that actually seats well. Then I could probably get away with a huge amount of biomedia and just a sock filter.

Does anyone know the recommended particulate filtration minimum size in microns? The filter socks I was looking at come in a range from 1 micron (1/1000 mm) to 100 microns (1/10 mm).

After more research, it looks like a 10 micron filter should be plenty (if not slightly overkill) in a tank that doesn't get stirred up too much. I should probably still use some kind of prefilter material. I have some rough foam that should work leftover from making roof vents.

So... Scrapping those containers. One or Two five-gallon buckets, a long length of 12 in. sewer pipe, or... something. Any ideas?

I obtained some new materials today. I asked my dad if I could use some of his pvc leftovers (he keeps everything) and while searching through, I found a pile of pvc well casing pipe and fittings to fit it. So I now have a 5 foot long piece of 4 in. pvc with caps and fittings that should work. I may cut off three feet to use instead, as five will be hard to hide.

I am going to use a screw-on type cleanout cap for the top and a 45 degree 2 in. inline fitting on the end (reduced to 1 in. nipple) for the output of the filter. The input will be through a 1 in. bulkhead at the top. The pump will sit outside the filter at the bottom.

I will most likely use vent roof foam and filter floss stuffed into a long 5 micron filter sock for mechanical filtration and either pot scrubbies or ceramic rings for bio.