You will want to run a general test to get an idea of the hardness, pH,
and the levels of ammonia, nitItes and nitrAtes. The hardness and pH
are good to keep in mind when selecting fish. The ammonia, nitites and
nitrates are toxic substances to your fish. I don't know if you are
familiar with the 'cycling' process. I will let other people get into
that more if you need more explanation.

Before you go spend more money on an air pump, try setting it on
something else. I had a air pump that was sitting on a wood shelf. The
thing shook itself right up against the cabinet edge and made quite a
raquet. I placed one of those silicon pot holders under it. It is now
much more quiet.