In my experience, rubbernoses (Chaestoma sp.) are territorial and omnivorus while the bristlenoses (Ancistrus sp.) are peaceful and strictly vegetarian. Both max out at about 4" in size according to Planet Catfish
. The Ancistrus claro (LDA0
, if you can find it, doesn't get any larger than 2".
You will most likely not be able to find properly identified Ancistrus sp. for sale. They are usually sold in mixed grab bags. Specific L-number Ancistrus sp. fetch very high prices that appeal only to catfish enthusiasts and not to us utilitarians. The Chaestoma sp. are a bit more organized, with the Chaestoma cf thomasi being the most commonly available. I was lucky enough to find a juvenile Ancistrus claro in a shipment two years ago. To this day, it's only 1.5" long.
Nonetheless, both are plant-friendly and wonderful for cleaning many types of algae, including green spot algae, off of glass and broad leaf plants.