We have Sir Bob the betta in a small 1.5 and are going to move him into something larger. He appears to be a fairly happy fish and loves human attention. He doesn't flare often, usually to his own reflection (once at my really colorful shirt!). How would I know what to look for to see if he would be overly territorial? What could be put with him safely? Husband is driving me NUTS about this but I love Bob dearly and want what is best for him.