should I add another pim?

[river17]

I have two pictus catfish living with a bristlenose pleco, and some medium sized tetras in a 55 gallon tank. I know that Pictus cats prefer to be kept in groups, but that there is a certain amount of competition in pairs. I have noticed bit of this though it is not severe. they will generally share shelter, space, and food. But when the larger of the two is feeling irritable he drives his fellow catfish out of her hiding spot and forces her to one of the less protected parts of the tank. the catfish are usually very active but because of the relatively bright lighting during the day they sometimes like to rest for a few minutes. their prize place is underneath the broad leaves of one of the large artificial plants I keep in the center. some of the leaves form a kind of cave that they have taken a liking to. when they are not swimming around crazily they are either there or in their second favorite hiding place that is far less protected. it is in the corner of the tank behind another plant, because they don't seem to like the cave near the front (too small perhaps?). sometimes they will share their spot but sometimes the larger one chases the smaller and does not let her return, but the smaller does get fed and in fact was the first to realize that she would get more if she had a feeding frenzy at the surface. I am still a bit worried that the smaller individual is being harassed at night when it is harder to observe them. I think that they would be less dependent on the hiding places in general if they had another catfish with them and the chasing would not be focused on just one fish. But I am not sure if it would be a good idea because the tank is already populated. it might also backfire and create more competition even though pims are peaceful. last but not least my pims are already 4-5 inches long, and adding 2-3 inch young catfish into their midst might not be the best idea. Also it might just be the lights that are making them possessive of their shelters and dimming them might be good. I would like to know if I should in fact add another catfish into the tank and if it might help.

[Richard B]

In my experience these always do better in groups - larger the better - ideally half a dozen minimum. As a pair the dominant indiviual will always be a threat to the other either by direct harrassment in one form or another or will have the other fish constantly aware of their presence making it difficult for it to settle fully. This is spread out in groups so no individual suffers directly as dominance of an individual is asserted across a number of individuals.

for a relatively small species i recommend these are kept in larger tanks than people imagine, a 4 foot is ideal & can accomodate a really good sized group. This is because they need an area of uninterrupted free swimming space and a few separate areas of cover, apart from each other. If a 6 foot is available, cover is hardly ever used and they prowl around constantly. if your tank is not too deep dimming the lights may help or having some floating plants or surface anchored roots etc to create shady spots etc

[river17]

Thanks! I will add some surface cover to dim the lights and at the very least add one other pim.