Please Help

basically im the biggest flowerhorn noob out there
my uncle just gave me 3 flowerhorns ... but i don't know what they are or how to take care of them or how much they are worth
can someone tell me

here are some pictures




sorry for the low quality picture
the tank is a little dirty
i am putting them in a larger / cleaner tank today and will take better pictures later tonight / upload them

but in the mean time, this is all i have

Brand New To Hobby

i never had a flowerhorn before
but im really interested

i live in the u.s [southern california]
i dont know where to buy the fish
but most FH ive seen thats from california, it doesnt have the bump on its head

can anyone please help me? where would i buy one with a nice color + large bump

another question is ... i have a tiger oscars, would it be ok to have the flowerhorn stay in that same tank? my tank is 125gallon

please help, thanks!