What Fish To Get?

You'll get better with the vacuuming as you get more practice.

I have found that it is next to impossible to prevent the fish from interfering.  You are kicking up the stuff in the substrate and they are investigating in case there's anything they can eat.  You have to careful because you can end up siphoning one of your fish out of the tank!

To prevent expelling dirt when you withdraw the siphon there are two things you can try.  First lift up the siphon from the bottom and let it run for a while just sucking mid-tank water.  This should flush all the crud into your bucket.  Second, put your finger over the bucket end of the siphon before lifting it up.  This may prevent the stuff being released back into the tank (or it may not depending on how lucky you are)!

PS.  This is not a post regarding "What fish to get".  You should really have started a new thread for this query.  It helps, both you and other people, with searching out interesting bits and bobs and not having to plough through 28 page threads with loads of different subjects.