cool, p's are cool fish to have, theres a general basis on 20-25 gallon per fish for them, but it really depends on how big they actually get(may not be enough)reds especially get big and fast too usually around the 8-10 inch mark. for them ide suggest you go long not tall on the tank,they really need the side to side and front to back swim space. theyll want to hang out at the bottom alot aswell which means their will be some uprooting on your plants.(they can be prety skitish and bang around at times) also try to get them as small as you can,that way theyl get used to having youre tank lights on them.as far as plants.....people usually recomend a variety of swords, maybe some kind of moss dwarf sag? the limiting factor being the amuont of light youll have... go for what youd like to see delicate stems will most likely get broken though...gl