Actually, I knew all along the T wouldn't work...
, that's why I advised against gluing anything initially.
. I'm sure Tony knew that as well, hence he suggested you do this when no one else was around...
Oooops. Once again Tony and I battle it out for the status of "the village idiot".
Definately stay away from a check valve ! They require maintenance and anything that is difficult to access get's put off for "another day"... It's just human nature. When I used one, maintenance was put off for "many days". Well o.k, many years...see my post titled,"thank god for shop-vacs..."
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You could use a couple of 90's to bring the outlet to the surface level but that would signifficantly reduce your flow...
. Cap the bulkheads and go over the back. You can incorporate a closed loop in the future...