Tropical Fish Aquarium Temperature

Is it the temperature or pH that causes temporary blindness and death in my tropical aquarium?

I recently realized that my Disco tropical fish swimming as if they were blind because they kept bumping into each otherr and runs on the sides of the aquarium obviously could not see! The tank temperature is 32degrees C. idblindedd afraid my fish to raise the temperature so it is down to 28degrees C. In the morning he could see again and I did a test of PH. The pH is pH 7.2, while pH6.4 down to what is recommended, but all my angels are dead! I want to add other angels, but first I need some advice. Please someone can help me?

32 C is about 90 F. a range of 80-84 degrees F is acceptable ... but the absolute maximum is 90. Besides pH and temperature ... What are the levels of ammonia, nitrate and nitrite ... ensure that they are also in excellent condition. 90 degrees is way too hot angelfish. could be your problem with them. 75-86 is a range of temperatures well. be of the order of 28 c ... is what is too low. But if you lower the temperature or raise the temperature too quickly (instead of a few degrees at a time ...) that might point to the separation. Its pretty hard to be in the water too hot, but for a sudden cooling down, it really underscores. When the temperature is too high or too low, whether ammonia, nitrates and nitrites are off if the pH jumps largest to smallest on the right just too fast ... stress and can kill fish. stability as an essential means of keeping fish healthy. This does not guarantee 100% that they never have problems but it is a good start and that stress is an important factor in making sick fish, and a lot of stress from the instability of the water. the first thing you should before adding to the angels ... More get the temperature of solid at the proper temperature for all the fish in your tank ... obtain the pH under control and keep it there (without advanced fast) to keep other levels of control, without peaks ... ensure there no signs of illness (ick parasites, for example) and then once you have everything under control and can not keep it there for at least one week, and all other fish look good, eat and swim normally and then add the fish. disease you describe sounds like "eye" Cloud ensure that no cloud fish eye that is before the introduction of new fish. Various agencies (not specified), the severe stress, malnutrition, cataract, aging, overproduction of mud due to poisoning, poor water quality, or irritation. General symptoms of the eyes is cloudy a mist before the eyes, blindness, lethargy, loss of appetite.