Good plan. Use an underground sprinkler control box at each "T". I would place a pressure gauge near the compressor and at the far end of the run to help troubleshoot problems later. 2 compressors would work, just make sure you have a one way valve close to each compressor so that if one under performs the other that you won't be back feeding into the poorly performing compressor. You may want to put 2 or 3 or 4 ball valves equally spaced down the main trunk line in those control boxes too. That way if a critter chews into the trunk line, or a fitting comes apart, you can shut down part of the system and not have to shut the whole system down, and that will also help you ID what part of the trunk line has a problem (leak). Use as few connections underground as possible. I had an underground sprinkler system that I installed in the ground in the middle of summer when it was HOT out. After a few years, heat/cool cycles pulled it apart at various fittings. I didn't realize how much the plastic line in the ground expanded/contracted with temp changes.

As for the compressors, I would use Gast Rotary Vane. They output more CFM per hp than others and since you shouldn't see more than 6 psi in the system, they should work just fine. Make sure you have over pressure pop-off valves near them set at 15 psi, and really concentrate on getting fresh air to them when they are running to keep them cool. Heat will kill them quickly - it will do that to ANY compressor.

You want to look at the CFM vs. pressure curve of the compressors, you will need at a minimum 1 1/4 cfm for every 9" membrane diffuser disc at 5 psi back pressure if you are using the diffuser discs from Vertex. I don't know what the requirements are for other mfg discs. Vertex did all their testing with 1 cfm to each disc, so the extra 1/4 cfm is a fudge factor. If you need parts/pieces to DIY the system, shoot me a PM. If I feel that something is less expensive NOT from us, I have no problem telling you that. For instance, if you are doing a DIY system, I'd buy the underground sprinkler control boxes locally at a plumbing or irrigation supply house.

Brass ball valves are way superior to the plastic ones, and are a LOT easier to turn. Again, source locally at a plumbing contractor supply place and not a big box store.

Use 0.5"-0.6" ID weighted tubing going to the diffusers. You will need between 8#-10# to keep a single membrane disc in place.

Put the diffusers in the deepest part of the pond like you have them shown.

When putting the barbed fittings in the black poly tube, I would put a hose clamp on the tube, then use a heat gun to warm the tube, shove the barbed fitting in the tube and use a 1/4" drive impact driver to immediately tighten down the hose clamp while the tube was still relatively soft. You will get good clamp force that way.


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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).