The pressures of 5 and 8 are telling us that when the system is running with valves partway closed it creates 3 psi back pressure which is not optimum IMO. Try to operate the system so the gauge is 5PSI as Ted suggests, which will help allow the "internal cups" to last longer because they and the motor bearings are operating with slightly less pressure (stress). Every little bit helps IMO.

Ted provides a good way to bleed off excess pressure. I by nature do not like to waste the air, thus I usually suggest the pump be on a timer and boil the pond with full air for about 2 turns then let it rest until the next day. Most relatively new low organic laden northern ponds will not loose the DO on the bottom to get close to anoxic condition in 24 hrs until the next daily run cycle. More southern and warmer ponds I am not experienced with. IMO the stronger churning can more quickly mix the entire pond compared to a slower gentler mixing. I've found from testing that both operating methods can work providing the pond is not hypereutrophic.

Last edited by Bill Cody; 07/27/13 09:33 AM.

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