I'm still waiting for my tank to cycle and since I managed to get the ammonia a little too high, I did a partial water change. I'd read and heard that the Python was good for water changes so I ordered one and it came today. No problem! I love this thing. Didn't spill a drop! Wish I had a utility sink so that I could leave it attached permanently, but it's not hard to set up. I highly recommend it! *thumbsup2