Originally Posted By: snrub
One minor issue I want to point out is that the diffuser will get "lighter" as air is applied to the system. At least with the round membrane type diffusers. I'm not familiar with the tube type.

The reason is when air is applied the membrane will "balloon" out some (the higher the air flow, the more it will balloon) and make it more buoyant than when you initially sink it without air applied.

Not a big deal, but if you weight it just enough to sink during installation it might float when you apply the air pressure to the system.

Another "not big deal" but "could become a problem" is if you have large CC or turtles they at times can move stuff around. If it were me, I would want it weighted more than just barely enough to sink it. You want it to stay in place. The reason I mention this is during my pond build I installed some cover that were made of plastic. I weighted them with a rock. No problem, they stayed down fine. Till my CC got to around 3-4#. Now once in a while I will find one of these plastic structures, 4 years later, floating along the bank to where the wind blew it after it floated to the top. I can only assume something (fish, turtle, what have you???) moved it enough to tip the ballast rock out of it and it floated. Like I said not a huge deal. Just part of the learning curve of "things you didn't think of but wish you had of".


I didn't think about the diffuser getting lighter as it inflated!! Mine are the tubular type. So far everything seems to be staying put tho and I don't have anything large enough to move things around...that I know of anyway...or yet.

Thanks for pointing that out!! I'll have to keep an eye on things and add some weight if it moves around. Good thing about milk crates is you have lots of anchor points to add more ballast if you need it.

.10 surface acre pond, 10.5 foot deep. SW LA. The epitome of a mutt pond. BG, LMB, GSF, RES, BH, Warmouth, Longear Sunfish, Gambusia,Mud Minnows, Crappie, and now shiners!!...I subscribe!!