I have just got home from work to find the end of my filter spray has blown off therefore creating no oxygen in the tank I have lost one fish which I am devastated about (my Colombian zebra plec) and am terrified of losing more, I changed the filter sponge chopped some off half the old filter as originally thought this was the reason before I saw the end having popped off. My other half is currently in the process of doing a water change to add some oxygenated water, is there anything else I can do? I am so worried for my fish!