I know it's an old thread, but a good one anyway.
If you think freshwater is bad, try cleaning a brackish tank. It's just that tad bit worse. I personally use the 'fill the hose with water first and use your thumbs to get it going' as well, just because I got too fed up with the water in my mouth. My other half still uses the sucking technique and can actually do it without getting any water in his mouth at all. Practise I guess.
As for the OP actually being serious about the question. I don't know, I can see why he/she would be though. I did wonder the same thing first time I got a lot of water in my mouth and felt sick for a couple of hours after.