Just a sowing of seeds for the more adventurous among us. These filters are our preferred filtration for anything over 100G, but we build them into most 4 footers from 75G up as well. The upside of this type filter is that it can be built on either end of the tank or on a rear wall, and unlike the pics shown, needn't take up the full tank width (see pic 3). In addition, there are NO externals except a single electrical feed. Tank installation is exceptionally clean and free from placement limitations. Filtration will do for ANY fish load with minimum modification. The filter can be surprisingly small - typically it will take up a maximum of 7 gallons in a 100G tank (this would be a big filter for an overstocked tank), but that same 7-10 gallon filter would comfortably handle up to a 300G tank with slightly more filter media loaded. This using of internal tankspace is the ONLY downside of these filters though, as it mostly limits them to bigger tanks. But after some time spent with all the different filter options (sump, wet/dry, canister/HOB) I personally have no interest in anything else.

First pic - the basic glasswork - you can silicone sized, cut glass pieces into the basic compartments quite easily. There are a few tricks - like using adhesive tape to hold the panes in place while they dry and one or two small features that I will PM anyone trying this out, but this is really basic DIY and easier than building stands and canopies!!!!


This is a 75G tank. Inlet compartment is on the left. The rear wall of the filter (grey mirror coating) joins the right hand wall of the tank, but the left edge of the filter rear wall stops a couple of mm from the left hand wall of the tank and a thin gap is left all the way up the tank. So the entire left side of the filter acts as the inlet - a full-height inlet that filters all of the levels of the water column evenly. A noticeable side-effect is how clean the tank floor stays. No vortices, no noise, very little flow restriction so you can run any size or combo of pumps on the outflow.

Pic 2 is a similar filter with media and equipment in place:


Water flows in left, upand over compartment wall and is drawn down through floss, then carbon, then bio media (white) and at the bottom a mix of zeolite and lava rock as a final bio-media. Right hand wall of centre compartment has a gap at the bottom where water flows out into outflow compartment. The outflow can hold 2 pumps if required, and you can really tune the return/returns any way you like. This tank has a single return coming in below the water line, so an air-pump is included for surface agitation. But again, you decide on how you want to feed back. Some tanks return through under-gravel jets only!! Then the outflow compartment can be made smaller.

Pic 3 shows a tank with inflow on the right, angled filter side-walls to maximise useable tank volume. This filter is on a 6 foot 180G tank.


Last pic is a 600G show tank. This tank has 2 internals on either end total volume 32G.


Now the good part - maintenance consists in removing/replacing floss every 2 months, carbon (optional) every year, half of the white wadded bio-media every 2 years. That big show tank has been up 3 years with nary even a rinse of the filter media. Now add up the costs of the parts: Glass a couple $. Silicone the same. Heater (?) - you choose the size/price, filter media (and here you can use the media of your choice, but pot-scrubbers work fine) costs about the same, and factor in how big/many return pumps you need.

Result: Something to think about as all you need to start is a bare tank of your choosing, a tape measure and some medicinal fortification to prop up flagging courage. As an aside, we run samll versions of these filters on many LFS stock tanks - 30G and up, but this is a maintenance-based decision.

Tremendously useful thread Cycle. Nice Job

Folks, that is very similar to the filtration on my 110 gal Tenecor acrylic tank. I havent cleaned the media since I set up the tank back in the spring. The only difference is the Tenecor set up uses some bioballs rather than the lava rock- but its the same principle. Cycle basically built the exact same thing that people spend hundreds of dollars on when they purchase a Tenecor set-up.

Fantastic job Very good read!!!

(a few weeks ago I did a huge water change in my Tenecor and my water was cloudy the day after... which never happens. I realized the next day that I didn't fill the water level in the tank enough to fill up the filter completely so I was operating on only 50% efficiency )

very...very...very cool D.I.Y. post.

Interesting.
Pete

Very nice cyclequip