dirty pond

We are new to this pond stuff. So any and all help greatly appreciated.
I just went into the pond to bring up the plants we sunk for the winter and
found most of my kitty litter that we used in pots is on the bottom of the
pond. Guess fish somehow got in and moved it out of pots. Any way to keep
them from doing this?
So I am trying to scoop it out, and also finding lots of guck. Think algae
and waste. Water is now so stirred up and bad can't even see 1/2" into it.
What can I do to get it cleaned up now?? We have 4 pumps that we put
filter material around and we just set in the pond and they pump the water
up to a water fall. I am running one now to keep fish alive ( I hope).
Should I run or them or let every thing settle out.
Thanks for the help.


--
Greg &/or Kellie Meyer