Thank you for taking the time to reply . My idea is that by putting a pipe on the intake line of a canister I could rough up (thereby increase gasious exchanges) the water going into my filters, allowing for more bacteria . I was reading about what breaks down ammonia/ nitrites into something safe bacteria!Do you mean on the intake or return side? Durso was created to quiet reef sump plumbing, not for oxygen, and from what I've seen some people have to do a lot of tinkering to get durso plumbing quiet and working properly, especially when they DIY the durso. So, either way, I don't know what it would accomplish, except to complicate your plumbing and either add noise or reduce flow efficiency of your canister, at least as I understand durso.
On the return side, there's a difference between flow and turbulence. You can improve oxygen efficiency of outflow simply by angling spray bars to create turbulence instead of smooth flow at the surface. I do this by lowering my spray bars and pointing them slightly upward, not by elevating them above the water line and pointing them downward-- quieter that way. It's not so much flow rate as turbulence that lets filter outflow oxygenate a tank-- a point missed by some who think filter current doesn't work well to oxygenate a tank. Everyone has their pet theories or understanding of oxygenating tanks, bubbles vs. filter flow, etc-- but, in fact, to make filter flow efficient you want the effect of riffles over rocks in a mountain stream from your spray bars, not a smooth flowing river. Or you can add bubblers.
..but for years most of my tanks do just fine with filter turbulence alone, you just have to get the outflow right.
In any case, it's your whole system you want well oxygenated, then you want efficient flow dynamics in your canister (not letting a filter get overly dirty) and correct order of mechanical vs bio media (primarily mechanical first) so your bio media gets clean instead of dirty water. Beyond that it's not a question of trying to achieve special oxygen conditions inside your canister vs the rest of the tank-- at least this is true in aquariums, the theory or approach might be different for a pond or water treatment plant where the scales and economics are different.
Yes that air flow is what I'm thinking in the filter. If it's doing that going down to the pipe and being drawn through will it create air pockets?????Agree with neutrino, and would add (if you try to add bubbles inside the canister, if that is your intent) bubbles inside the can would create condition for the pump to cavitate, detrimental on many fronts.
I have found venturi's valuable on the outflow of returns, especially when keeping rheophilic species.
Although I don't find most canisters have pumps strong enough to do this.
Below the kind of turbulence from a venturi on an outflow.
Don't know if it's what you're intending, but this sounds almost like a quasi-moving bed concept. I've done moving bed filters before and like them, but they require different media and flow rates than a canister. More advanced media experts (not your typical hobbyists) will tell you that you don't want to clean or rinse conventional bio media too vigorously, it's actually not a rare mistake. It disturbs or removes beneficial bacteria and can cause a 'mini' cycle. This seems to argue against too much turbulence within a canister. Canister and moving beds involve different media, flow rates, and principles, I don't know that you'd want to try and hybridize them. Not to say it's your intention, but what you're describing sounds like it approaches it.
Which gets back to simple observation and conventional testing should tell you what you need to know. Low tech, high tech, old school, your own invention, or whatever, you're not going to do better than healthy fish with normally steady, relaxed breathing (except when there's a lot of chasing or fighting), no ammonia and nitrite and low nitrates. However you get there is up to you.
