| This was when I first introduced my lobster into my tank and I was certainly concerned that the actions my BGK was showing was going to turn into more of a problem but the tables have turned and I've found that my lobster was causing all sorts of problems for my tank.
I have recently and relunctantly returned my lobster to the pet shop. My lobster, BGK and Rope Fish all decided that they wanted to share the same cave all though there is plenty of hiding spaces for all three to have their own space. My lobster had been slowly hacking away at my BGK's anal fin and he seemed to be very stressed and was looking to be in quite poor health. I was almost sure I was going to lose him. It has been about two weeks since I returned my Lobster and my BGK is getting back to his old self quite quickly.
A warning to all others out there as well that might be interested in a lobster; he is a menace and will eat any fish he can catch. I've lost about 4 fish in the two months I had him and I had a couple of live plants that were all chopped off at the roots from his claws. If you do get one I recommend having very quick fish as anything that is a slow moving fish will disappear.
As for my BGK, I have not had any problems what-so-ever. I do not keep any small fish in my tank as I have several large mouths in my tank. My BGK, Rope Fish, and Pictus all have mouths large enough to eat anything that is smaller such as neon's. Very soon I will be getting an African Butterfly Fish as well and these guys have very large mouths and will certainly eat any small fish. | 
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