bz, sounds like its going well. The 10 inch height is about perfect.If you have a blue 3/4 inch "Brady" checkvalve either on the intake side of your airfilter or in the water at your stone setup see if it still has the spring in it. If it does remove it and you may drop to 10psi.AES started removing the spring a few years ago but I still find a few units that have them. Also if you do have this valve untread the end of it to expose an oring that seems to only last a year or so. It may be cracked.Lastly I always found the yearly cleaning (per instructions) much needed on these stones as the vane dust wanted to collect on the inside of the stones and lessen circulation and increase back pressure especially on the units that are considered high pressure and do not have the internal carbon vane filters. Even with the filters the dust will collect in the stones as it gets pushed through.You should be in good shape for that pond expansion,