You could build your own. That's what
I did. The supplier I used for the diffuser discs has a High Capacity model for $16.
Here are the stats from that disc
Model: 9" High Capacity
Peak Airflow: scfm 10.0 m3N/h 15.8
Design Airflow: scfm 1.0-8.0 m3N/h 1.7-13.6
Diffuser Diameter: in 10.9 mm 276.8
Active Surface Area: ft2 0.4 cm2 381
Unit List Price: $16.00
Stocked: Yes
Note - design airflow is 1-8SCFM per disc. So you could build your own with 2 discs and less than $20 worth of PVC plumbing.
Zip-tie it to a concrete block and your in business.
I looked at quite a few linear pump performance charts and they almost all loose about 20% of rated CFM for the first 5 feet of depth and 60% at 10 feet...
Barry
