System question for my pond systems questions pond boss forum gas vs electric oven running cost

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Your compressor, if in good shape, should output XX amount CFM at a given depth. The deeper the water, the more the back pressure on the compressor, the lower the CFM. As was pointed out, about 6 psi is what your pressure should be at the compressor head to be able to push the air out against the static water pressure at thhe 12′ depth plus what resistance is in the line and diffuser. So if the pressure reading is significantly higher than that electricity bill nye, something is amiss.

A membrane diffuser is sized and has holes to operate correctly at a given CFM flow (actually has a range of acceptable operating CFM flows). If there is more air flow (to high CFM) than the holes and size of the diffuser can handle, it will balloon up and force the holes bigger, reducing the output of the compressor at the higher psi while at the same time over flexing the membrane. This will cause the membrane to fail prematurely, like a balloon being over inflated.

IF this is the case (and it might not be, just check the specs on the diffusers for their CFM rating). The output of your compressor at the depth it is running (12′) should fall within the range of the sum of all the diffusers added up can handle. If you have more CFM than what the diffusers are rated for, you can either add more diffusers (like a dual, triple or quad diffuser), use a bigger diffuser, or bleed off some air from your compressor so not all the air goes gas prices in michigan to the diffusers. I personally would want to use all the air you are paying electricity for to compress, even if it meant going to bigger holes and bigger bubbles or a larger or multiple diffuser. But that is just me (and I am not at all an expert).

Like I said before, I’m no expert. I have run pond aeration for a total of two or three weeks last fall as a temporary experiment in preparation for installing a permanent system later this spring (soon I hope). My knowledge is mostly from reading a bunch (here on PBF as well as mfg spcs) last year in preparation for installing a system myself. But I have had many years with pressure and flow rates in hydraulics and air so have what I feel is a very good layman’s working knowledge on flows and pressures. I’m also a scuba diver and understand static water pressures at depth. So that is the background I speak from. Definitely not from years of experience with pond aeration systems.

My opinion would be, where you have had a fish kill, you want to clean up some muck, where you are in remediation mode, my OPINION would be you could use all the air you could get. You might stir the pond up and make it turbid with old muck. So what? Nutrients stirred up should give you a good algae bloom. It might make your water look yucky for a while, but the added disturbance should get you the quickest results of remediation.

After all what does the air do? It moves water. The bubbles 2015 electricity prices don’t do much themselves except move water. The bubbles are inducing current to move water. I don’t see any way (and I have been wrong before, many times, so it is an opinion, not expert advice) that you could produce too large of current in the water to hurt the current fish population or do any permanent damage. If you don’t like the results being obtained, do something different.

I think each Vertex diffuser should take all the air direct from the compressor with 0 back pressure. Ask Ted to connect gas station near me open one of his single diffusers to a 4cfm pump and see what his psi reading is. IMO pressure should be 0 not 10psi. Something seems wrong with this picture IMO. A normal Vertex diffuser should not cause that much back pressure. The only way the psi should be 10 for one diffuser is the holes/slits are smaller than 1 millimeter and too few of them on the membrane.

Bill, I may be all wet here because I am speaking from what my minds eye sees and not from practical experience, but I would expect more back pressure from the diffuser at shallow or no depth than from deeper depths. For example, at 10 feet depth, the compressor already has to overcome the static water pressure at that depth. The diffuser might only add an additional tenth psi or something very small to open the slits for the bubble to escape. But I can see where there is no back pressure from water depth, it is going to take something to balloon up the diffuser and cause the air to escape.

I do know if you connect a dual Matala diffuser to a pump at about 4 cfm it will balloon up when done so on the surface. Did not gas jeans usa have a pressure gage installed at the time (have one now). I have not watched it at depth (will this summer when I scuba dive the pond – will try to remember to take pictures) but I would expect the membrane to move very little. Seems I read somewhere it is not particularly good to balloon up the membranes as it is hard on them.

It has always been my experience and preference to have no or very little back pressure (0-0.5psi) on the pump when a diffuser is connected to a compressor. This is very important when building your own diffuser. You ideally want all the air to escape out the diffuser with no pressure on the gauge until you start putting the gas examples diffuser in the water. If there is back pressure on a home made diffuser, you don’t have enough holes in the diffuser or the holes are too tight/small or both, i.e too much air trying to get out too few or too small of holes. My thinking is why create unnecessary back pressure for the pump??. Use all pressure to operate the diffuser.

snrub says: but I would expect more back pressure from the diffuser at shallow or no depth than from deeper depths. For example, at 10 feet depth, the compressor already has to overcome the static water pressure at that depth. The diffuser might only add an additional tenth psi or something very small to open the slits for the bubble to escape.

From actual practice there is no backpressure from the diffuser at no depth. If there is any back pressure out of the water it should not come from the diffuser. What would create the backpressure? Generally it is due to too few holes or too small of holes, or too much air volume trying to get through too few holes. You say The diffuser might only add an additional tenth psi or something very small to open the slits… This is correct. Very little psi is needed to open the slits, similar to a check valve. Low pressure should be needed to open the valve. At 10 ft the static gas in oil pressure washer or water head pressure needed to release air is 5psi. IMO very little extra pressure of force should be then be needed to open the check valve and slits on the diffuser. PSI to open slits plus head pressure, plus tubing back pressure/resistance equals total pressure on the air gauge. Back pressures are additive. Is all this clear as mud???

It has always been my experience and preference to have no or very little back pressure (0-0.5psi) on the pump when a diffuser is connected to a compressor. This is very important when building your own diffuser. You ideally want all the air to escape out the diffuser with no pressure on the gauge until you start putting the diffuser in the water. If there is back pressure on a home made diffuser, you don’t have enough holes in the diffuser or the holes are too tight/small or both, i.e too much air trying to get out too few or too small of holes. My thinking is why create unnecessary back pressure for the pump??. Use all pressure to operate the diffuser.

snrub says: but I would expect more back pressure from the diffuser at shallow or no depth than from deeper depths. For example, at 10 feet depth, the compressor already has to overcome the static water p gasol pressure at that depth. The diffuser might only add an additional tenth psi or something very small to open the slits for the bubble to escape.

From actual practice there is no backpressure from the diffuser at no depth. If there is any back pressure out of the water it should not wholesale electricity prices by state come from the diffuser. What would create the backpressure? Generally it is due to too few holes or too small of holes, or too much air volume trying to get through too few holes. You say The diffuser might only add an additional tenth psi or something very small to open the slits… This is correct. Very little psi is needed to open the slits, similar to a check valve. Low pressure should be needed to open the valve. At 10 ft the static or water head pressure needed to release air is 5psi. IMO very little extra pressure of force should be then be needed to open the check valve and slits on the diffuser. PSI to open slits plus head pressure, plus tubing back pressure/resistance equals total pressure on the air gauge. Back pressures are additive. Is all this clear as mud???