Small Strange Bubbles

Question
hello, i have a 55 gallon fish tank and it is occupied by a tiger oscar and pleco.  i had another oscar and he ended up dying, got a white decaying like substance on his fin, tried meds nothing helped, i believe he died from an infection from some cheap goldfish i bought him, anyway i got anohter one now, hes small like maybe 3-4 inchs long, the pleco never got sick...but yesterday i noticed the pleco had a bunch of little bubbles on him that would fall of if he swam fast, and saw a few on my oscar today..i change/clean the water once a month about 25-35 percent change, so i just changed the water and i saw some of the bubbles on what looked like a hair stuck in the rocks, any thoughts?

Answer
Hi Daryl,
 First, you need to be doing much more frequent water changes.  You should be changing 25% of the water once a week, every week to keep your fish healthy.  Secondly, NEVER feed goldfish to an oscar. Goldfish almost always carry various infectious diseases such as ick and oscars catch these very easily and typically die from it.  

 When you put the new water in the tank, are you using cold water?  If so, that would explain the bubbles, it is oxygen coming out of the cold water as it heats up.  You should be putting in water roughly the same temperature as the existing tank water.

-- Ron
  rcoleman@cichlidresearch.com
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