I noticed one of my Albino cory has some red marks to it earlier today. I have been busy with work but had enough time to run a quick Ammonia and Nitrite check - both are fine. I haven't had a chance to run a Nitrate check yet but it should be okay, the tanks been cycled for a number of months now. Last water change was Sunday evening. Any help appreciated as I am at a loss - one of them did get caught up in some Java Moss the otherday and I had to free him (then trim it!), I wonder if it's a wound, but I don't know if it's the same fish. Shall I run a water change today to be on the safe side? I do them Sunday evenings usually.