their water clouds up in 3 days!

Question
Every time I clean my fish, their water is so cloudy I can't see them in about 3 days.  I have a 15 gal tank with 5 small/med oranda's, 1 black moor, 2 "poop-eaters", and 1 small algae eater.  I have a filter made for a 20-60 gal tank (I plan on upsizing soon), I know I don't overfeed that much, and I have had them for almost a year now.    They had ick a while back, and I gave them medicine for it, and they got better.  Since then, I can't get their water clean.  It gets so cloudy (within 3 days!!) I can hardly find them to catch them.  I have had fish for a while, and know a good bit about them, but I have never run across this.  What do I do to save my fishies?  

Answer
How do you go about cleaning your tank? Do you stir up the rocks or use a syphon hose? What are you putting in your tank? What kind of food (I find some types of algae foods cloud the water) do you use?

PLease send me some of this information, and I will get back to you, thanks!

From Stephanie