Idea for DIY filter

[Dark Morelia]

Hey All-

I've come up with an idea for a filter, and i've drawn some plans for you all to have a look at.

Intended for Biological filtration.

"Hang-on Canister Filter" ?

The diagrams are a bit sketchy (ha ! get it?) so i think some explanations are in order.

Intended materials are 4-6" PVC, with the bottom lid cemented on, and the top lid screw-on. Flexible hose going from pump outlet to fitting on side of filter, but with PVC for the inside bit.

I haven't yet figured out how it's going to hang over the back of the tank, but that should be easy enough. It will stick up a couple of inches past the top of the tank.

I thought maybe sit it inside a larger bit of PVC, which can be drilled, etc. for stronger attachment.

Would the bacteria get enough oxygen in there ?

Any ideas why it won't work ?

Any suggestions for improvements ?

Any constructive criticism ?

Anything at all ?

Cheers,

Andy

[Ash]

Of course it will work, except for the location of the pump essencially that's how canisters work anyway isn't it?

The only thing is the power head would need enough grunt to handle the small amount of head height involved, you'd probably want at least a 1000lph unit anyway and they usually have at least 1.2m head height so you would be laughing.

[Guest Gutty]

You could fix it to you cabinet/stand with some horse shoe type brackets, they make them specificly for the PVC sizes.

Also, why put that pipe down the guts of it ? I think it'd be much easier to simply put the inlet fitting down the bottom and the outlet at the top(or vise versa) and simply flow "through" the chamber rather than down then back up. Would save some work IMO.

Have you considered running it horizontally along the back of the tank ?

[mianos]

I would also, as gutty suggested, pump the water into the top. More like my moster version here:

monster reactor

If you use standard 23mm pressure tubing you can drill a few holes in an endcap and make a sprayer that will gather much more air as it flows into the top of the media.

[Dark Morelia]

Hey Guys,

Thanks for the replies.

The filter in there ATM is 1400lph, so it shouldn't be a problem, but if it is, then i have a spare 2000lph.

The idea behind the inlet tube down the middle was so that i could just disconnect the inlet hose on the outside, and then go clean it without having to drain in it in situ.... but seeing as it's biological I won't be cleaning it out too much, will I ?

So i might just put the inlet hose at the bottom of the canister as sugested by Gutty.

I don't really understand how the water would circulate through all of the media before exiting, if i had the inlet spraying water onto the top ?

Unless i had the outlet on the bottom, in which case, how would it get back to the tank without another pump ?

Would it help if i ran an air tube into the bottom of the canister ? would that give bacteria enough oxygen ? or is it the water spray that really counts ?

Gutty's idea of horizontally sounds good, it could spray in then, and still just run out the other end.

But the thing about having a spraying mechanism, aren't they noisy ? the tank's about 5 feet from my bed.

Thanks for the replies guys !

Cheers,

Andy

[mianos]

As long as as water level in the container can be higher than the water level in the tank without running out anywhere else (i.e. the floor) it will run out the bottom into the tank.

If you use and endcap to make a sprayer you can add/remove/size holes for the level of noise you want by drilling more/less larger/smaller holes. The fun bit is to buy a few endcaps at 50c each and experiment. I have made them silent.

[Dark Morelia]

Would it flow back into the tank at the same rate it goes in with this method ?

If i used the same diameter hose as the inlet ?

Andy

[Fins]

I don't really think oxygen would be much of an issue. If a regular canister doesn't need the extra oxygen, I can't see why this design should need one.

The only thing that I can think of is that most canisters "pull" the water through don't they? Whereas this design "pushes" the water.

I don't know what effect that will have.

[BaZ]

I like Gutty's horizontal idea

You could really have one along the entire length of your tank if you wanted.

If it is biological you are aiming for, I wouldn't worry too much about sprays etc, as long as you are keeping the canister full you will always have water in contact with the media.

And yes, as Fins says, don't worry about oxygen. All the best canisters in the world are sealed off from oxygen

Arrange the return from your filter so that it agitates the water a bit, creating ripples. That will give you plenty of oxygen in the water.

[bishop]

A thought.

If the filter is horizontal you will have a lot more difficulty getting all the air out. You will need to bleed it out at hte top somehow. The vertical option should not have this problem.

[Fins]

A thought.

If the filter is horizontal you will have a lot more difficulty getting all the air out. You will need to bleed it out at hte top somehow. The vertical option should not have this problem.

If the pump is "pushing" the water, then that shouldn't be a problem I don't think.

It only becomes a problem if the pump if "pulling". In which case, the "canister" needs to be primed.

[Dark Morelia]

I think i will still go with the vertical positioning.

If oxygen isn't going to be a problem, then i might keep it as it is.

I did consider having it just sitting on the top of the tank, with the inlet at the top, and the oulet at the bottom, but i think it would just look too untidy. (although that would match the rest of my room )

Andy

[Guest Gutty]

Good point about the air getting trapped.........though an air bleed valve could easily be installed.

Please keep us updated on this DM, i'm very interested to see how it goes.

[23Skidoo]

I've read through and alot of people suggested putting the inlet from the pump directly at the bottom of the canister.

I think the original idea of the smaller pipe running down through the centre would be best, as if the pump fails, wouldn't the water in the canister (with the pressure of the water above) backflow to the pump? And this would drag all that pretty brown goo into the tank/pump. Plus like you said it would be alot easier to clean/disassemble as well as build, because it removes the need for making a water tight seal.