One of the altums, since a couple of days ago does not seem able to close his mouth. I was kind of hoping it would resolve without doing anything but is still the same. The first day I saw this it did eat some, but today it does not seem to be eating, otherwise it looks normal and is swimming around with the others. I have googled this and found a lot of posts, mostly saying to catch the fish and see if it has anything stuck in its mouth or throat. But I'm scared to do this, I am afraid I might damage the fish. But I might have to - any advice? what would I use to examine the mouth, and how would I hold the fish without dropping or hurting it?