Hi guys, I fed my minnows some freeze dried blood warm (read to eat) this morning for the first time and almost instantly the bubbles on the surface increased massively and haven't gone down. I've done a water test and all is well there, I've taken off the filter and the air stone to check them, they all seem fine and I've done a bit of a water change but they're still there. The tank is a BiOrb and if it wasn't for the stong air flow the surface would be covered in these bubbles. It's only the surface movement that is keeping the middle area bubble free. It's not done this before. Is it something to do with the blood worm? And how do I get rid of them? Thanks in advance. Get rid of the bubbles I mean not the blood worm, they've eaten them all. Would changing 20% of the water help? If so is it safe to leave it until tomorrow so the treated water can sit for 24 hours to get to the right temperature?