Hi,so i want to put in my 65gallon tank a mespillia globulus urchin a fromia indica starfish and a sand shifting starfish but i was worried because i've read that the fromia indica starfish eats algae along with detritus and other small organisms.I have around 20kg of live rock in the tank and dead aragonite for substrate.The tank was running for about 8 years but early november i think the tank made another cycle.So is it ok to put the urchin and the 2 sea stars together in the tank?