Petland in Carmel/Westfield (off of st rd 31) has a pretty good selection of fish. The last time I went there, their plant selection abslutely sucked. THere were decaying plants in the tanks which were overran with algae.
The Reef (56th and Keystone) has been going through some changes within the past few times I was there. They are adding in more display tanks and getting their plant selection back in order.
Members of the CCAC get discounts to specks, the reef, and a few other places here around town. Personally, the discounts alone will quickly pay off the yearly 20 bucks membership fee.