1) ALL SPECIES OF PLECOS ARE DIFFERENT! Some like muddy, hot, slow moving water (Stripes Peckoltia). Some like crystal clear, fast moving water that is a little cooler (Blue Panaque).
2) All Plecos have different food requirements. Some eat algae. Some are carnivorous. Some are scavengers. Some eat wood. Most will eat a combination of the above.
3) Some Plecos can be aggressive to other fish, especially slow moving or sick ones. The most aggressive are the Gibbiceps. Royals can also be somewhat aggressive to each other, but rarely to other fish.
4) Many Plecos can grow quite large, so make sure that you have enough aquarium space for them to grow into.
5) Coloration in Plecos can be remarkably different within a species, depending on the region where the Pleco was caught.
6) Most plecos show some characteristics of chameleon like color changes depending on their background (the L060 Lyretail Chameleon Pleco and the L110 Red Spot Bristlenose are good examples), so keep that in mind when you set up their aquarium.
7) Many, if not most, are good community fish. Ones we recommend the most to keep with slow moving fish such as Discus and Angelfish are the Bushy and Bristlenose. Some of our other favorites are Striped Peckoltia, Snowball, Clown and Royal Plecos.
8) While it does seem to be counter intuitive, Plecos can be jumpers, especially the Bristle and Bushy nose. We recommend keeping the water tanks with Plecos about an inch and a half below the rim.
9) The best Internet reference for Plecos is Planet Catfish who’s link is http://www.planetcatfish.com/core/