i have 2 btas already i want to add a purple LTA as i have a credit with a vendor and they got one in stock im wondering do they wonder much? i was lucky enough to where my btas stayed in the spot i chose for them also do they like medium or low flow? and do they like to put down straight into the sand or maybe with their foot on rock crevice maybe if i pick the right spot it wont go wondering stinging all my corals