DIY PVC filter

Rob24

Rob24

AC Members
Apr 21, 2003
67
0
6
http
So, I have been flopping around a DIY PVC filter in my head. Let me see if I can explain my thoughts... lol

One large diameter PVC pipe. I'm thinking around 6" - 8". Length would not matter to much. I'm thinking about 12-20 inches give or take really not important. I would glue two threaded screw caps on either end (for easy cleaning) Use Teflon tape for a water tight seal. Would attach some sort of bulk head on either end one for intake and one for return. I have not fingered out what to use for the media baskets. I would want to use something that fits nice and snug, as to not let water around the basket. I would put an in-line pump just before the filter to push water through the filter. This would have to be a fairly beefy pump to push against the filter. I picture this laying horizontal under a tank. Out of view.


One problem I can foresee is how tight I can get the media packed into this thing. Loose media will result in a lot of by-pass...not very efficient.
This intake side would almost have to be rigid pipe. To keep it from getting sucked together/closed.

Being that it is a closed loop system I would not have to worry about a siphon problem. (??)


I'm sure I forgot about something.
Any thoughts are welcome! I'm not an expert at anything.
 
sounds like a good start. but im pretty sure you could just pack the media in the the eheims. just use some mesh, then bio, then mesh.
 
I have been thinking about the same sort of filter.

What I had thought was a longer length of PVC that could be fitted into the hood.

A powerhead with a sponge prefilter sits in the tank and pumps water up into a filter tube, maybe a 3 or 4" tube packed with biomedia. Ceramic biomedia wont pack down, so you could fill a 4ft x 3" plastic tube with it and just pump water though it. So you have maybe 3/4" plastic tubing attached to both ends, one coming from the powerhead, the other ending in a spray bar. A removeable screw cap on one end would allow you to dismantle the filter for cleaning if needed, but the sponge prefilter would keep most of the crud out.

The filter could sit on brackets in the hood and have some quick connect hose fittings?

Anyone else experimented with this sort of idea?

Ian
 
Hi Ian,
I think you're on the right track as well. The first thing that comes to mind. YOu would need a valve or some sort of resrictor so the pipe fills with water. If you had two holes the same size im not sure if the pipe would fill. Unless the pump was pretty powerful.

I would use a small pump and Your spray bar as a flow control.
 
been there, done that.

the problem is going to be the pvc screw-in end caps. they eventually start to leak from performing normal maintenance and become a bear to remove/replace over a fairly short period of time. it doesn't take long before thread tape is useless and replacing it starts to add up in price. at that point you might find yourself resorting to filling the gaps with more and more vaseline to fix the gaps created by normal maintenance.

surely an o-ring would be the cure to the leakage that's inevitable except the end caps that get glued to the pipe to accept the screw in caps are usually beveled on the inside leaving no place to put an o-ring or compression washer.

even if you figure out a way to get around the leak issue it won't be long before you have to hire a lumberjack to hold your filter while you crank away at the end caps with a pvc wrench. if you figure that out you still have to deal with the little square nipple/nut being stressed to it's maximum every time you remove an end cap.

i gave considerable thought to dividers for separating my media so-as to not restrict flow but never implemented it because it would have been a wasted effort if i could not open my diy canister without a team of mules standing on it let alone the inevitable leakage that ensues after so much maintenance.

i had a 2 stage setup with a 3" 2' and a 4" 2' chamber. i had the smaller one filled with bio media and the larger one contained my pads and floss. one other issue i was faced with was removing all the media since my arms don't fit in either size pipe. i worked that out with a cut up bent up piece of clothes hanger but that was soooooo unnecessarily tedious it was ridiculous.

i had both stages mounted under my (diy) cabinet with tie down ropes with a quick release piece that made them real easy to remove. at the time it was my crowning achievement and i was so proud. i had no idea how bad of a failure the whole idea was going to be. talk about disappointment. :(

i had drilled and tapped threads to accept threaded hose barbs on both canister stages and my diy pvc intake tube reinforced with thread tape of course. little did i know i could have purchased a sufficient canister for the price of the taps alone. not only that but i had a rio 2100+ pulling the water through and even had the little spinning top with 2 outputs/deflectors to reduce water pressure yet still maximize/optimize aeration and surface turbulence. it was fancy, costly, overdone and yet a huge failure. i felt like an engineer who just discovered a huge breakthrough... useless, lol.

in the end the pump i eventually sold to a local shop for much less than pennies on the dollar for store credit cost me (after selling it and minusing what i got for it) still more than the canister i replaced it with.

i almost forgot this whole engineering masterpiece was also a convertible ugf. i made myself a pvc plenum, topped it off with some screening and had shaved down a couple end caps as well as had a removable intake pvc tube with an intake filter over it. the plenum had a pvc coupler as well as did the intake. i was able to remove the line from the plenum, cap it off so nobody could get into it and just slap on the regular intake pipe in seconds. i would swap these back and forth depending on flow/cleanliness/muck in the substrate/etc..

just some food for thought.
 
almost forgot... i also implemented shut off disconnects from a magnum filter. i still use them since i have my heater and my uv sterilizer plumbed into the canister i'm so glad i replaced my masterpiece with. not for nothing but without them i think i would have been suicidal/homicidal over the degree of difficulty and issues created by the pvc canisters themselves.
 
Well, that was a kick in the nuts! lol and here I thought I was onto something. I just spnet the better part of an hour at Menards. I looked over every piece of PVC they had. Put this on that and even came up with some great ideas... So I thought. I'm glad I didn't buy anything. I was just in the pre-planning stages.
 
Problem with these projects is that it's like trying to reinvent the wheel. You can do it, but in the end you're left with a wheel!
 
The achilles-heel of any DIY canister filter that is under pressure is going to be the access lid which must be easily accessible, easy to reseal, yet able to withstand up to 14 PSI positive and negative pressure. This is why a round O-ring seated on the side of the canister is the primary sealing method of choice. A one way sitting on the rim (like the on my DIY) will leak unless strong clamps are used or the canister is sitting along side the aquarium at neutral to very low PSI (1-3 PSI).

Mine worked for months very well along side my aquarium and cost me about $50. But I could never place it under the tank without adding bungee cords to seal the lid with force. Bottom line I learned allot about canisters and I considered the PVC pipe idea but I remembered how difficult it is to un-thread PVC fitting once in use for any length of time and conversely how easily the threads leak when not welded, overtime line vibration due to running water will loosen them up just enough to allow leakage yet require a bear hug and banging to completely un-thread. This link shows mine that worked great now retired due to limitation of pressure. Now I leave the initial designe up to manufactures, buy used and make modifications which is much easier and cheaper LOL.
http://www.aquariacentral.com/forums/showthread.php?t=191499&highlight=lock+seal
 
You must log in or register to reply here.
AquariaCentral.com
Top Bottom