I find they don't do well in pairs as Duane mentioned since there is nothing to distract the male from the female. Years ago, before I knew better, I kept a pair in a 90G tank and his relentless pursuit of her resulted in her "holing up" in an inverted flowerpot virtually all of the time, until he finally got to her. They definitely do best in groups and growing up together. In my 180G, I have nine adults (3 males, 6 females) and they coexist beautifully. They are sharing the tank with two adult menarambo, one dambabe, three grandidieri and one oligacanthus. One big happy family. Oh, and three young CAs, P. breidohri that make great targets (I find the polleni pretty bold and outgoing so no real need for dithers). They were originally feeders that managed to escape that fate. Now they are an important (although not a necessary) part of the dynamic. Remarkably, I kept two young pair in a 50G for the better part of a year. I was keeping them for a friend who wanted them but for reasons beyond his control, he couldn't take them. The tank was absolutely bare except for two sponge filters. Each pair took an end and rarely were no real issues. They are now in the 180G. My tank decor consists of driftwood and largish river rock much as RD has suggested. At one time I had plastic plants to help break sight lines and define territories but I've since removed the plants with no detrimental effect. The tank needs a good water change but here's a pic or two.
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