I checked the box again. It does say AquaClear 30 for 10-30 gallon tanks...and in little print at the bottom, which I missed before, it says "Formerly AquaClear 150". Aha!
I got nervous because my box doesn't look like the boxes on the online sites that sell the AC
filters. The ones they show are white boxes and have different model names. My box (and all the other AquaClear filters at PetSmart) is bright green. I guess these are the new models because they all had "Now With BioMax" in a bright yellow bubble on the front of the box. Anybody hear of this? It seems to be a new layer of these pellets in a mesh bag, that go above the carbon and sponge layers.
I also noticed a big price difference, da*n it! I got mine at PetSmart for $27.99 and the AquaClear 150 they still have on their website is like $15! Holy crap. Doubled the price just for the BioMax layer and the new boxes?! Argh.
Anyhow, thank goodness I checked here and had great advice on how to minimize the media replacement costs. Of course they want you to "replace" all the stuff every 1-3 months; no suggestions in the manual about just rinsing out the sponge or getting floss cheap!