Paddle wheel aerator

[MikeinCO]

Hi all,
This is sort of (well, really) an off topic question, but I can think of no better experts to ask than Paddleducks paddlewheel forum members. I'm interested in your advice on how I might build a miniature (roughly thumb-sized) paddle wheel aerator for use in oxygenating small aquariums. I need it to be easy to build (I regret to say, I'm not an electrical/mechanical engineer), submersible (because it will sit on the water's surface), and efficient (ideally battery operated). To give you an idea of what I mean, below is a description of a full-scale device used to aerate catfish ponds. I'm grateful for any help you can offer, from step-by-step instructions to links to other sources that might help me continue my quest.

Thank you!

"Another method this is utilized in North Carolina is the use of paddlewheels to circulate massive amounts of water through the pond economically. One such paddlewheel, using a 3 hp electric motor and turning 9 rpm's is pushing approximately 10,000 gpm's of water through the pond. The paddlewheel itself is made up of a central shaft with 8 spokes of angle iron to which is attached 2×8 boards that are 8 feet long. The paddlewheel is boxed into a baffle, or recirculating levee so that there is about a 1 to 2-inch clearance for the paddles on the sides and bottom. The theory of using this type paddlewheel to circulate large amounts of water economically is that you improve the water quality through the turbulent movement of the water. This keeps the water from stagnating and also adds dissolved oxygen. Paddlewheel aerators, such as those used the catfish industry to aerate ponds have also been tried in crawfish ponds to improve the dissolved oxygen levels. Although they are more efficient in adding oxygen to the pond, they are very inefficient at pushing that oxygenated water through a crawfish pond. To date neither type paddlewheel has been thoroughly tested by researchers to determine the ultimate impact of these aerators on the water quality in a crawfish pond." (source: http://washington.ces.ncsu.edu/crawfish+pond+flooding)

[bill stafford]

what i would do, is make the p wheel out of H.I.P.S tyrene sheet,glued together w plastic model glue, not to big ,drive via tooth belt, to remote motor/gear box , less than 100/50 rpm, to reduce water splash, paddle wheel 100/150mm O D.
 if you could do it, a hand speed control would allow you to fine tune its speed .
there are a number of suitable motors on ebay.
good luck

[MikeinCO]

Thanks for your very helpful reply, Bill. Is there a motor you might recommend, or one I could look at as an example?
Best,
Mike

[bill stafford]

gday mike,
 motors are a hard one , with the shut down of graupner and robbe, there is a BIG hole in the market.
 you need to work out the revs ,I would say 50/100rpm, even make a simple hand control speed control, but it does need to be geared down ,as a direct drive motor will heat up and draw too much amps , hence the use of tooth belts,as another means to gear down motor,and build torque-at 300 rpm you will be throwing water all over the place.
there are a lot of motors on ebay ,from hong kong,w g/boxes ,in the 10 rpm range,as long as your paddle wheel isnt over 120/140mm OD,they should be fine, you will just have to try 1 ,and see, aim for high torque.
dont try to use O rings, they tend to slip a lot
aim for a 37mm diam. motor, 545 type, to get enough power/torque
jaycar has simple speed control circuits,as does most of that type of shop
next question ??
regards bill

[MikeinCO]

Bill, this is great information - gives me plenty to get started with. I'll get to work and, if you don't mind, I might hit you with a follow up question if I hit a wrinkle along the way.
Thanks again!
Cheers,
Mike

[bill stafford]

no worries mike, by the way , were are you ?? australia or other ??might make it easier w product supplies.
the critical issue is the rpm ,so look hard at the specs+you want a 37mm od motor ,if possible , same as a 545 motor ,not brushless , as you need torque, not revs
bill s
by the way , there are HIPS kits available from Float a Boat au ,for paddle steamers ,plenty strong enough