betta tank 25% water change each time

Question
Hello again Ron,

Thank you for your previous response to my question regarding tank cycling and sanitizing plastic gravel.  I have a further question regarding changing 25% of the tank's water each week.  If I'm just scooping up a quarter of the water from the top won't the fish's waste and any other debris that sank to the bottom of the tank remain in the tank and thus keeping the water dirty?  I know you mentioned that by changing a small amount of water this would keep the beneficial bacteria in the tank.  But what about the bad stuff that would also remain in the tank?  I hope this doesn't sound like a stupid question as "logic" seems to tell me that the water would stay filthy because I wouldn't be able to take out any waste just from removing some water.  Thank you for helping me out!

Cheers,
Nikki

Answer
Hi Nikki,
  It is always a good idea to use a gravel vaccuum when you are removing water from the tank during a water change.  You want to get the stuff at the bottom. You should not just scoop water from the top of the tank.

  I assume that you have a filter in the fish tank, right?

-- Ron
  rcoleman@cichlidresearch.com
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