Ok so the formula is for cfh not cfm. Most fans I see here are rated in cfm so figure 400-500cfm is plenty - overkill really enough to do 3-4 air exchanges per minute. Flip flopping between autopots and the Wilma. Even though the only Us Wilma source in the US that I could find is almost double the autopot cost, i'm leaning in the Wilma direction ATM. I had to go back and reread the first 10-20 pages of your Wilma thread to get a better idea of what's what. Did not realize the
@Itisi had a Wilma too. Had to pop over and read the first 20-30 pages of his latest tome. I don't know if the experience left me any more enlightened but it's been a good read so far. Do you still aerate the res and check and adjust the ph daily.