Bigger, Better Tank; Gone Horribly Wrong. (Please Help)

Just added around four or five smaller mollies into the large tank; all seem to be doing fine, although the filter current seems a bit too strong for them.
 
gobies tend to be more sensitive than the mollies
 
you mention you tested for chlorine. are you using the dip strip tests? they are horribly inaccurate and i wouldn't use them if somebody paid me to.

what you want to get is the API Freshwater Master Kit. it is a liquid regent test and is considered the best on this forum.
 
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