so in my ten gallon i have 5 neon tetras and 1 balloon molly (I know he needs a bigger tank) is there anything else i could put in there like some corys or maybe a guppy or two, or am i already fully stocked? i have live plants in there (hornwort, java fern, moneywort, anacharis, amazon sword, and some other plant that i cant remember what its called.) i also have a gravel subtrate.