fish and cloudy water

Question
Dear Jamie,
  I don't know what kind of fish to get for my 25 gallon aquarium.  It's freshwater.  Also, I've had the filter in my fishless tank running for almost a week, and it's never been cloudy.  Then just this morning i woke up and the water was much cloudier.  Why and what can i do to make it clear again?

Hardy

Answer
Do you have any fish in there right now?  Do you know what cycling is?  Here is an article on what you should do before adding fish.  

http://badmanstropicalfish.com/articles/article14.html

Also, you could add biospira or filter media from an established tank (one set up over 3 months) and be able to put fish in right away.

What kind of fish do you like?  do you like the larger fish like gouramis or angelfish?  do you like smaller fish like tetras, rasboras or guppies and platies?   It's really sbout what you like.  Some guidelines are:

1.  1" of fish per gallon of water
2.  Stay away from plecos and "algae eaters"  They get too large for a 25 gallon. If you want an algae eating fish, get a school of otos or a snail.
3. tetras, rasboras, platies, and guppies are schooling fish and need to be kept in 6 of each species; 2 neon tetras, 2 blackskirt tetras, and 2 glowlight tetras won't cut it...you need like 6 neons etc.
4  I would try one "centerpiece fih" like an angel or a gourami and then add some nice smaller dither fish.  An example would be an angel fish (6") 6 green fire tetras (12") 6 male guppies (6") and a couple otos (otos take up almost no bioload)

Another possiblity would be a gourami OR a betta (2-3") a school of rasboras (6 of em) and a couple of dojo or killi loaches.