Position of Pleco Mouth

     If you observed closely, different species of fish will have different mouth position. The mouth position of fish, whether it is angled up, ahead or down actually correlates with the trophic ecology of the fishes. The majority of fishes have terminal mouth regardless of trophic habits, which means that their mouth opens forward.  Any deviation from the terminal location of the fish's mouth will usually indicate that their different feeding habitat.

     Compared to other fishes, the Pleco's mouth is positioned on the bottom , which means their mouth open downwards when feeding. This type of fish mouth characterizes the fish as algae eaters or bottom feeders. Fishes with such mouth are termed inferior or subterminal, where most of them belonged to the catfish species.

     One amazing fact about inferior mouth fish is that they too can feed on food that is floating on the water surfaces. Believe it or not, they can position themselves in an upside-down position if the food does not sink to the bottom.

     The video below showed a rare video of our Pleco feeding upside-down on the cucumber we feed them every day. YOU REALLY HAVE TO SEE TO BELIEVE IT!! NO JOKE!!!

Reference

1. Helfman, G., Collette, B., Facey, D and Bowen, B., 2009,  The Diversity of Fishes: Biology, Evolution, and Ecology, 2edn, Wiley.