The proper dosage for Coppersafe is 5 ml for every 4 gallon of actual water volume. The target copper level should be 1.5-2.0 ppm
. When looking through the test tube, look through the side and hold it beside/just above the color chart. Be sure you are in good natural lighting and not fluorescent.
Signs of stress would be lethargy, color loss, appetite loss, swimming in front of powerheads and so on.