I recently tested some fine pore Sweetwater diffusers for CO2 dosing.
These produced better consistency in terms of bubble size and smaller bubbles than the Azoo/Ehiem and other disc type of diffusers(both were new for the comparison, time will see how both behave, but the consistecy is better at this point). They also have more gas volume per unit than disc do as well and there is little to no back pressure.
One idea was to place on the smaller air stones inside the return line coming into the tank from a canister filter. This is very simple and they are about 1/2" square on a side at the smallest.
I've used the Rena air stones in the past, they are decent but these seem to produce better bubbles size consistency. They 1.70$ for the smaller ones and the larger up to 4.23$ from www.aquaticeco.
http://www.aquaticeco.com/index.cfm/fuseaction/product.detail/iid/9751/cid/2328
The small ones are all we need in most cases.
Plus Aqeco has dang near everything.
The small one is as good if not better than the best Azoo disc.
The goal is to reduce backpressure and maintain flow, venturi valves like Kent's 1/2" model constrict flow too much(flow rates of 180-1800gph). By making a larger(say 2-3") tube section to place a mist stones or a powerhead driven venturi, the mist can be added.
You can make your own venturi inlet fairly easily also. Take a smaller input line(say1/2") and connecting it to larger out line(say 3/4") and adding the gas inlet right after where the different sizes meet will mimic a venturi(there is a pressure differential between the different tubing sizes and that is what causes the venturi) Simply using a piece if rigid air line tubing and melt the tip some to reduce the orifice size and adjust into place.
I've does this with air in the past, but not CO2, but should work the same.
It is also simpler than the atomizer idea with the 2-3" tubing etc.
I have hooked up the Ultra fine mist duiffusers from Aquatic Eco and these are very very well built and far superior to anything I've ever seen as far as a disc(ADA, any brand you can think of or can find). You'll never wear these out or break them. The space for producing the mist is much larger than any disc sold today and and the pores are much finer(hence the nmeed for backpressure..
http://www.aquaticeco.com/index.cfm/fuseaction/product.detail/iid/9775/cid/2339
This produces very small and very consistent.100-500micron bubble size.
The largest bubbles from these are the smallest from a disc.
At 55$, these are serious misting units. I use Tygon tubing since the backpressure is higher(25psi). To clean them, bleach can be used, but most just take them out and give the stone a light sanding, back it goes.
If you have a 100+ gal tank(up to a 500gal tank or so) and a good source of current, these will supply the mist very well. Better than any other stone/disc. Cost less than an AM 1000 reactor also. Or go with 2-3 of the sweetwater diffuser stones.
I cannot say how impressed I am at the quality and ablilty of these ultra fine bubble plates as well as the Sweetwater diffuser stones. Better than the Azoo and the other disc I've tried out.
The Sweetwater stones are about the same cost as limewood, but appear to produce better bubble sizing. We will see how well they hold up over time. So far though, they seem easier to use, less backpressure, 10X or more cheaper.
They are only 1.70$ea after all.
Regards,
Tom Barr
www.BarrReport.com
These produced better consistency in terms of bubble size and smaller bubbles than the Azoo/Ehiem and other disc type of diffusers(both were new for the comparison, time will see how both behave, but the consistecy is better at this point). They also have more gas volume per unit than disc do as well and there is little to no back pressure.
One idea was to place on the smaller air stones inside the return line coming into the tank from a canister filter. This is very simple and they are about 1/2" square on a side at the smallest.
I've used the Rena air stones in the past, they are decent but these seem to produce better bubbles size consistency. They 1.70$ for the smaller ones and the larger up to 4.23$ from www.aquaticeco.
http://www.aquaticeco.com/index.cfm/fuseaction/product.detail/iid/9751/cid/2328
The small ones are all we need in most cases.
Plus Aqeco has dang near everything.
The small one is as good if not better than the best Azoo disc.
The goal is to reduce backpressure and maintain flow, venturi valves like Kent's 1/2" model constrict flow too much(flow rates of 180-1800gph). By making a larger(say 2-3") tube section to place a mist stones or a powerhead driven venturi, the mist can be added.
You can make your own venturi inlet fairly easily also. Take a smaller input line(say1/2") and connecting it to larger out line(say 3/4") and adding the gas inlet right after where the different sizes meet will mimic a venturi(there is a pressure differential between the different tubing sizes and that is what causes the venturi) Simply using a piece if rigid air line tubing and melt the tip some to reduce the orifice size and adjust into place.
I've does this with air in the past, but not CO2, but should work the same.
It is also simpler than the atomizer idea with the 2-3" tubing etc.
I have hooked up the Ultra fine mist duiffusers from Aquatic Eco and these are very very well built and far superior to anything I've ever seen as far as a disc(ADA, any brand you can think of or can find). You'll never wear these out or break them. The space for producing the mist is much larger than any disc sold today and and the pores are much finer(hence the nmeed for backpressure..
http://www.aquaticeco.com/index.cfm/fuseaction/product.detail/iid/9775/cid/2339
This produces very small and very consistent.100-500micron bubble size.
The largest bubbles from these are the smallest from a disc.
At 55$, these are serious misting units. I use Tygon tubing since the backpressure is higher(25psi). To clean them, bleach can be used, but most just take them out and give the stone a light sanding, back it goes.
If you have a 100+ gal tank(up to a 500gal tank or so) and a good source of current, these will supply the mist very well. Better than any other stone/disc. Cost less than an AM 1000 reactor also. Or go with 2-3 of the sweetwater diffuser stones.
I cannot say how impressed I am at the quality and ablilty of these ultra fine bubble plates as well as the Sweetwater diffuser stones. Better than the Azoo and the other disc I've tried out.
The Sweetwater stones are about the same cost as limewood, but appear to produce better bubble sizing. We will see how well they hold up over time. So far though, they seem easier to use, less backpressure, 10X or more cheaper.
They are only 1.70$ea after all.
Regards,
Tom Barr
www.BarrReport.com