Toys are actually a good idea. Flowerhorns tend to get bored. Mine would spit water and gravel out of the tank to grab my attention.
Sexing is easier to tell if you look up pictures. They have particular differences in fins and their vent shapes. I would say to look up pictures. Females can also get a kok (the hump) too. And some males never develop a kok. So, that's not always the best way to tell.
And the sizes are all pretty up in the air. Because they are hybrids, there is a pretty big stretch on how big they get. Some will stay around eight inches and some will push towards twenty. It depends on their genetics and from what I have read, there are freaks that pop up every now and then.
Bare bottom tanks are pretty common when seeing pictures of people's flowerhorn. Many are breeders, so a bare bottom tank is easier. Or the fact that they are crazy interior decorators.
Good luck with yours!
55gPLANTED:Rainbows/Loaches/Garras|30gVIV:Crestie|20gL:Leos|10g:Pearl Fighter|5g:Betta|5gChi:Spark Gourami/Badis|5g:ADF|2.5g:Betta|2.5g:Betta|