What you need to know about Sucker Mouthed Catfish (Pleco’s)
#1 Pleco's Poo... Pleco's poo a lot. Not just a lot, but a lot a lot...especially big ones. In all seriousness, they really do produce a lot of waste and add a considerable amount of bio-load to any tank. This is something to consider when keeping large Plecos with some of the messier "chew-and-spew" Cichlids!
Meat Eating Pleco?!?-Not all Pleco’s are the same.
There are many common misconceptions about the fishes we often call “Pleco’s” (any fish from the family Loricariidae). One of the most common misconceptions regarding Pleco’s is that they are all basically the same fish, but with a different “paint job”. This couldn’t be farther from the truth. Coming exclusively from South America, the family Loricariidae is a highly diverse group of catfish with many specialized species. A good example of this diversity is the differences between the "Zebra Pleco" Hypancistrus zebra and the "Royal Pleco" Panaque nigrolineatus. "Zebra Plecos" requires a meaty "high protein" diet where as "Royal Plecos" eat wood almost exclusively. (Yes, you read that correctly...they eat wood.) A Royal Pleco fed meaty foods would either starve or bloat from the high protien, where as the Zebra Pleco would quickly starve if only fed wood and greens.
Let’s take a look at some of the more commonly available species:
“Common Plecostomus” (Now:Pterygoplichthys spp. often P. pardalis or P. disjunctivus Formerly: Hypostomus punctatus and Hypostomus plecostomus)
This is the Pleco most often seen in your local fish store (LFS). These fish get large (~12 inches), can be aggressive as adults and produce a lot of waste. Common Plecos need a large, well-filtered tank with 75 gallons being the minimum recommended tank size. These fish are omnivorous but like a lot of “greens” in there diet. Common Plecos are not generally recommended for the Rift Lake Aquarium. Mbuna and other Malawi Cichlids tend to pick out the eyes of these fish, and most Tanganyikan set ups have too high a pH for this fish to be comfortable. Common Pleco’s are often kept with larger South and Central American Cichlids, however check the chart below for more specific compatibility information.
“Bulldog, Rubber-nose, Rubber-lip Pleco” (Chaetostoma spp. )
These medium sized (~6-8 inch) Loricariiads come from swift moving rivers and streams and require cooler, highly oxygenated water. They are omnivores and like a fair amount of protein in their diets. While not an ideal candidate, they can be acclimated to Rift Lake water chemistry if given a lot of "flow", but beware as Mbuna and other territorial Cichlids may pick on them. This is a great candidate for medium (or larger) sized West African Riverine type aquariums.
"Sailfin Pleco, Gibby" (Pterygoplichthys gibbiceps)
A "tank-buster" of a pleco, these fish can easily reach 18 inches and are only suited for the largest of home aquariums. As their common name suggests they have an impressively large dorsal fin and make for an attractive addition to large aquariums. They are omnivores but like a good quantity of "greens" in their diets. Not recommended for Rift lake set ups. They can be mixed with South and Central American Cichlids similarly to the "Common Pleco".
"Oto's" (Otocinclus spp.)
The pleco's in the genus Otocinclus are some of the smallest sucker mouthed catfish available. These little Pleco's reach a maximum size of around 2 inches depending on the species. Oto's do best in groups, are primarily vegetarians and do great work on algae. While excellent additions to most planted tanks, due to their diminutive stature they should only be mixed with the most peaceful of Cichlids.
"Bristle Nose Pleco" (Ancistrus spp.)
The common "Bristle Nose" Pleco is a medium sized, omnivorous species with many attractive line bred variants (long-finned, albino etc) regularly available. The males of this type pleco have large spines coming off of their noses giving them an intimidating appearance. While this fish normally comes from acidic to neutral pH waters it has been found to be tolerant of high pH and is often mixed with smaller Tanganyikan Cichlids. It is recommended to avoid housing these smaller (~6 inches) plecos in with larger, aggresive South and Central American Cichlids.
"Royal Pleco" (Panaque nigrolineatus) "Clown Pleco" (Panaque maccus) Assorted Panaque spp.
The genus Panaque contains the wood eating Royal and Clown Plecos as well as a number of other described and undescribed xylophagous species. These fish require wood in their diets, this makes keeping them in rift lake conditions difficult and they are best suited to soft water tanks with plenty of bog and drift wood. Care should be taken as some of the fish in this genus get quite large. Another word of caution is that these fish have teeth capable of eating wood. That means they can also scratch acrylic tanks, eat the silicone seams out of your aquarium and even munch through your heaters power cord.
"Zebra Pleco" (Hypancistrus zebra)
One of the most hyped and expensive Pleco's on the market these carnivores stay relatively small and peaceful. Considering the cost of this fish, I would not risk housing it with anything but the most peaceful of tank-mates.
"Goldnugget Pleco" (Baryancistrus sp)
This omnivorous species is one of the more popular "fancy" plecos. It likes warmer temperatures and care should be taken as these plecos can get to over a foot in length.
For more specific information on Pleco's and Catfish in general, be sure to check out http://www.planetcatfish.com