I had a 9004 great little skimmer. Skimmed well. Although I had to close the air valve all the way otherwise it would overflow. It appeared to have to much air for the body, that being said it skimmed well.
Another issue for me at least is the collection cup was to small. I had to empty the cup every two days. Being gone for a couple of days was a problem for me.
It was in a 30gallon tank with four damsels and mainly softy coral tank.
I currently switched to a JNS HOB.
If you have room for a larger skimmer I would go that route but if you are confined with space the 9004 is a nice skimmer.
Another issue for me at least is the collection cup was to small. I had to empty the cup every two days. Being gone for a couple of days was a problem for me.
It was in a 30gallon tank with four damsels and mainly softy coral tank.
I currently switched to a JNS HOB.
If you have room for a larger skimmer I would go that route but if you are confined with space the 9004 is a nice skimmer.