Hint: It's the same thing that was used in the Biosphere II project.



I was going to bring this homemade contraption to the convention for a demonstration but didn't make it. I hope to do an article on how to build it, and how it can be something a pondmeister can definitely use depending on his or her goals.

BTW I've got all the bugs out. There were some typos in the book Small Scale Aquaculture by Stephen Van Gorder that can throw you for a loop.

aerator/filter?

Some type of aerator. I see you can probably hook up a hose or something and you'll get a stream of water to turn that whole contraption to introduce air?????

Looks like a big version of the biological filter on my aquarium.

Chris, you win...

That is a RBC (Rotating Biological Contactor). The rotation is created by a diffuser placed underneath the RBC off a little in the front or back of the apparatus. The idea is to place only 1/3 of it in the water and the other two thirds is out of the water.

The idea is that the corrigated material gives a greater surface area for biological growth that will help to consume nutrients.
As it rotates, it allows the bacteria to absorb the nutrients and as it is out of the water it is absorbing oxygen. By rotating, one can ensure that there is even flow of water and air to maximize the bacterial community.

It is also known as "Bacteria Inn Express"

Now that I looked at the picture a little closer, it looks like this one was run by water pouring over the water wheel in the center.

Would make good spotfin shiner breeding structure too...

You're right Cary. This one rotates via water pumped back from the clarifier and is know as "Option 1." You can do the same by turning the frame upside down and diffusing air up to the paddles from below. That is known as Option 2. I preferred option 2 but a good quality air pump with the right PSI and
CFM's was about $325.00. With Option 1 will have to add an aspirator or agitator but it's cheaper than the air pump.

The book this is in is outstanding and covers everything from RAS to cages to flow through and Aquaponics. For only about $25.00 it's well worth it.

Available on Amazon.com. The title of the book is Small Scale Aquaculture by Stephen Van Gorder.

AKA wet/dry bio-filter.

Cecil, I would think a small aquarium air pump would be sufficiant to turn it---slow turning is ok (sometimes better) as long as it doesn't dry out entirely.

Maybe so, but with Option 2 the air pump specs call for more air production at 2.2 cfm/1 PSI pressure at 27 inches of water and the closest I could find in the AES catalog was a $325.00 pump. (Sweetwater SL56 page 45.)

I think more air is needed than an aquarium pump to also run a airlift system (two pipes from two drums) to move water from the clarifier back to the main tank since there is no water pump.



The water goes to the clarifier via a siphon. There are also airstones that provide aeration that must receive air from the pump. See below:

BTW I like the way 4 inch PVC halves line up to form the paddle wheel before the other side piece is glued to them. Kind of cool eh?

Cecil, I was referring to a small air pump rotating the Bio-Wheel only.

I have no doubt an air-lift sytem would require much more volume.

I use air-lifts in my new facility in Ky. we use a 3hp regen blower ay 4psi.

I know you did, but I was making the point that more air was needed to make the whole thing work including the clarifier, which is why the $325 pump is needed.




Yes you're way ahead of me on this kind of thing. Would love to hear more about your set up.

I'm going there today and will try to take lots of pics if I get time. We are grading out over 7000 pounds of tilapia. Got a buyer for the ones over 1.2 pounds and a few for late season forage. Whatever doesn't get ordered will be mulched into the rows of grapes, thornless blackberries, and veggie gardens.








Too bad they're not GSF. All those scales glistening would be real purty in the Kentucky moonlight!