Fisthank Problems

Question
Hi, Because of the fact that i am no expert on fish and have no idea what is important, i will go into as much detail as possible. I have a 10 gallon fish tank with 6 fish in it, (one Dwarf Gourami, two White cloud fish, one male betta fish, and two fish which i irresponsibly forgot the names of, The tank is on my college dorm desk, and is not near any breezes allowing the temperature to stay pretty constant. I have a filter, which i just changed, and a boat for the betta fish to call his own. Other than problems between the betta and the gourami, which i will be solving shortly by removing the gourami, nothing has been wrong until recently. A few days ago the Gourami started to swim into the side of the tank, as if he was trying to escape though the glass. Now, all the fish except the betta fish are doing the same thing. There are 5 fake plants in the tank as well and gravel. I have not changed the water other than every once in a while topping it off because of evaporation (in an attempt to silence the filter). My two questions are if, A) is topping off the tank every week enough of a water change to keep Nitrates and other bad things out of the water, or should i be doing 20 percent every month like the lady at the pet store said. B) What is causing them to swim up against the side of the glass, is it bad, and how can i fix it. In addition the tank does not have a lid, and i use a De-clorinater when i fill it.

Answer
Hi Paul,
 You need to change 25% of the water immediately!  You then need to do that again tommorrow and again the day after that (this is not the same as changing 75% at once, which will likely kill the fish). After that, you need to get a regular schedule of changing 25% of the water once a week, every week.   BTW, topping up the tank does not do anything about removing ammonia or nitrates.

-- Ron
  rcoleman@cichlidresearch.com
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