Heavy Duty Aerator Pump

[Trex52]

Anyone know where I can purchase a HD aerator pump? I am having to design and build an aerobic septic system to treat effluent as the soil where I am, does not perc. It is that hard pan clay that makes rice farming so easy, so can not go with leach fields and such. So far I have two large plastic septic tanks in the ground (looks like underwater mines) as the primary anearobic, settle-out-the-sludge tanks. Then they go to a secondary cement ringed ( with a bottom) tank for any additional settling and then on to a tertiary tank that will house the aerator pump. I plan to have the pump on a timer and then another pump-out to disperse treated liquid to water the gardens and orchards. I live in Phayao and will probably have to venture up to either Chaingrai or Chaingmai to find anything that will work as things like this are impossible to find here. Thanks for any input. trex