you can actually put as many fish as you like but it really it depends on how big is your tank and how good is you're filtration system. imo, FH is not a good choice, you may consider though datnoids as aro tankmates. goodluck! :headbang2
i agree. its very hard to keep two asians together on a single tank especially RTGs. anyway, you may also try flagtail and redhooks as tankmates but stingray for me is still the best.