hey i have heard of some people switching impellers on their aquaclears i was just wondering what this actually does. does it slow down the flow? like if i put my impeller from my AC 20 on om AC 30 what would that do?
The AC 20 to 70 use the same motor, the impellers and size of the intake tube effect the flow rate. Physically they all are fit. But, due to the intake tube diameter typically one doesn't make more than a single size jump.
Example you want the larger box of the 50 on your nano but you don't want a Tsunami so you use a 30 impeller.
Some where on this forum there's another post on this topic and I added a Email from Hagen on this topic.