I have one that is just over 15"...have had him for just over 1.5 yrs now. I wouldn't suggest any tank mates that are the same size or smaller thats for sure. The only survivers out of all the fish I have tried is one giant sleeper goby and a pleco. The only reason the goby is still alive is because he is so damn wide and he stays in his cave. I had two goby's but the smaller of the two got owned! Every now and then I wake up and he has a huge chunk missing out of his head but the flesh always seems to grow back. Recently the goby has been trying to flex on my armatus too it's pretty funny to watch. I'll take some pics tonight...

