I bought one of these tonight, the Koralia 2, which says its puts out 600GPH. For the price i thought what the heck this should be fine to my 30 gal that i already have a Maxi jet 1200 in. After plugging it in it made a loud noise then started to run smoothly, but i noticed there wasn’t much added movement in the tank. The only thing i see moving more than before is a small curly Q nem. This thing wouldn't even kick up the sand from about 12in above it pointed directly at it. Granted it does not blow straight, but more of a circular spray movement.
Has anyone ever bought one of these or had the same problem that i am having? It just doesn’t seem to have the power i thought it would have.