My gulper ate two LARGE shrimp today and his belly is just so big. hes swimming around with his mouth open gulper water is what it looks like. is he alright or is there something wrong? usually he barely has his mouth open but now he has it open and is swimming around the tank. i added a half dose of mela and pima fix...hes in a 20g hes 4-5" long and has a AC50, a powerhead and a airstone for filtration. tank temp is 80*F