ASM G2 or G3


Premium Member
I have a 72 bowfront non-RR. This a reef tank with all softies at this point. I think I have a fairly light bio load in it. I have

1 Sailfin tang about 4-5"
2 Small Clowns
1 Lawnmower Blenny
Assorted inverts

I am going to buy a Lifereef overflow and add a sump/refugium. I was wondering what size skimmer to get. I am looking at the ASM G2 and G3. The only reason I am really considering the G3 is in case I ever upgrade to a larger tank as I feel the G2 would be more than sufficient for my current tank. I don't really have any current plans to upgrade tanks, but I don't want to get bit by the upgrade bug and have to go back out and plunk down $250 for a new G3.

In general considering a low, medium, and high bio load how large of a tank could be supported by a G2?

So for example say:
low bio load 150 gallons
Medium 120 gallons
High 100 gallons

I would appreciate anyones thoughts.
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New member
The G3 is twice the skimmer the G2 is. A G2 will take care of your system now, however, if you do upgrade in the future, a G3 could go with you.


New member
I have a G-2 on my 65 and I love it! It does a wonderful job. But yes The G-3 Is a much better Skimmer. Just make sure your sump can hold it!



New member
I just put a G3 in a AGA 20L sump. I was shocked at how large the skimmer is. It will fit but make sure you plan on making your own baffels. I'm setting up a 65 gal tank and went with the g3 so if I upgraded I could keep the skimmer.