View Full Version : DIY hospital tank filter

05-01-2007, 04:14 AM
Ive known this idea for like 2 years, but its time to spill the beans.

For a DIY 1-5g filter, you need the following

1x airpump
1xbubble stone attachment for end of hose
1x old plastic fish food container
1x a bit of polywool/filter floss
1x some gravel
1x some carbon (not necessary really)
1x 1" diameter hard plastic hose

First, clean the fish flake food container, and take off the labels. The container will not rot in the tank. Then, stick the 1" diameter hard plastic hose in the middle of the container, and hold it there, pressing down firmly. Then, add some gravel (and carbon if wished) around the 1" diameter hard plastic pipe so that the gravel fills 1/3 the fish food container. Then, stuff the rest of the container with polywool or floss. Then, connect the stone bubbler to the hose, and jam the bubbler down the 1" diameter hose so that it reaches the bottom inside the 1" diameter pipe. Plug in the air pump, and thats it. It serves all 3 forms of filtration if you include some carbon. It serves best as a filter for lightly stocked or hospital tanks 1-5g. It works quite well, and is just a fancy UGF design. PM me with any questions

05-01-2007, 07:46 PM
pics would be nice

05-01-2007, 07:57 PM
Can you please describe how it does the filtering? If i understood right, the air pump is blowing air into the gravel and filter material that are inside the container

Cuz i dont think that blowing air into gravel and filtering material acually filters water

Did i understand wrong? Like genitor said, I think a pic will help

Great Idea tho, once i figure it out, i'd like to try it! :thumb:

05-01-2007, 11:27 PM
i'll try to make a pic. Im leaving away until sunday, so it'll be a bit. the basic principle is that the water is dragged through the 1" pipe and goes through the polywool/gravel mix

05-03-2007, 11:28 PM
Yeah, not understanding how it will perform mechanical filtration. To accomplish that, you'd need water flowing through the media. If I am understanding your design though, only air (and of course the water that is being aggitated) would go through. You'd need to force more water through the media. And...well, I'll stop there. A diagram will be great when you get back!

05-04-2007, 09:49 PM
im still away, using someone elses computer. The bus ride was a living hell. someone had 1000 lbs of beans before we left, since it smelt like dead rat the whole way. Heres pics. Someone else used the same design


05-05-2007, 04:17 AM
if i understand the whole thing correctly, the water current is generated by the bubbling. However, i see this inefficient. Why not just use a small water pump?

05-05-2007, 04:58 AM
you could do that too. I found this way to work really quickly and well

05-05-2007, 12:31 PM
I'm quite sure you didn't mean this to turn into a debate, and I don't mean to be contributing to such in a negative way. I just don't see how air filtering through the media is going to make it a mechanical filter. You'd have to push water through the media. Maybe I just need to build one and see for myself.

Lady Hobbs
05-05-2007, 01:10 PM
The fish food containers are made of cardboard. How can they not get soft and fall apart?

05-05-2007, 01:13 PM
He's talking about one that is made of plastic. Otherwise you'd be absolutely right.

05-05-2007, 02:35 PM
cardboard? never heard of it.

Yeah, for sure use plastic

05-26-2007, 06:50 AM
lets see if i can describe this:
in an UGF, bubbles from the airstone pull water up the and then it flows back down the outside of the tube into the tank. In this situation, bubbles from the airstone pull water up the 1 inch tube. This water is, naturally, drawn from the water that the airstone sits in. In this case, its the water in the filter media. As this water is pushed away, it is replaced with water from the tank.

It is definitely a low flow solution, but it does the trick. I have a commercial filter like this that came with my 10g. Just bubbles an airstone to draw water through. I have another whisper internal filter doing supplemental duty (because the tank is overcrowded, and it was just sitting there doing nothing) that is also uses bubble power. Its only rated for 3 gallons, but it can still move water.

05-27-2007, 05:23 AM
mine worked really well.

6 months ago when my aulonocara albino got popeye from septicemia, i had him in a 3g hospital with no filter, just a airstone. when i made the filter, the water cleared up tremendously

06-07-2007, 05:41 PM
Zerileous gets it, lots of things use bubbles to create water flow. UGFs, sponge filters, the cheaper protein skimmers, small filters like those whispers, etc. This is just a DIY system that can be packed with whatever media you wish, and made to whatever size you require. Thank you cocoa_pleco, I'm sure I'll end up using this idea some day.

06-14-2007, 02:40 PM
I hate to add more criticism but I noticed on the link the guy said " This plastic is guaranteed to be fish safe because obviously it is intended to store their food". This isn't exactly true; fish flakes are dry but in water some plastics will leach into the water column. I'm looking at my can of nutrafin max and it's made of polypropylene but I suspect some are HDPE.