my fish are randomly dieing

Question
ok,i had goldfish for a while now and for some reason they are dieing the tank is 8 inches wide and 5 inches tall and about 8 1/2 tall to the tip my 2 of 3 fish died randomly died after i changed the water iv'e had them 4 about 3-5 months and been changing it the same(letting water sit 4 at least 24 hours and stuff like that)im a noob and my mom got me a fish and i dont know what kind it is but i will give u exact detail the fish is about 3 inches long and dark blue or black on the bottom of its stomach it is silver i came home from school and there it was dead but the weird part is it canged color it was kinda goldish my mom insisted that it was a goldfish and could eat gold fish food but i dont know.....i have 2 other fish that died and they were about 1 inch long(regular g.fish and they randomly died (thats why my mom got the new one)please help me im really p.o.ed now

Answer
Well, it may be possible that the water you added was not declorinated. Sometimes letting the water sit does not eliminate all the clorine, so if you did not declorinate it I would definately get a declorinator for the water. Also, if you did not declorinate it I would suspect the clorine for the reasons of death for your fish. Next, your tank is small and it may have been overcrowded and this can also cause death. Finally, the fish could have had a disease or parasite. You should have known from signs like: salt-like spots, bumps, fuzzy patches, not eating, not swimming normally, cannot balance, clamped fins, torn fins, red marks, and other odd signs or colors or behavior. Other than these reasons, I would not be able to tell you another reason other than the fish were from a bad store. If they were from a bad store they would have been weak or sick when you got them and then died from the stress. However, while the fish are dead and it is nearly impossible to tell why, focus on starting over. Completely clean the tank and all the equipment and decor. Replace the water with clean decloronated water. You do not have to let it sit but do be sure to get a declorinator for it. Let the tank sit without any fish for two or three days, then add one small fish. Let that sit for three or four days and if all is good, add a few more. Do not overcrowd and do not overfeed. Also, be sure you know what fish you have to be able to feed them the right food. Feed goldfish, goldfish food and if you get other fish you will need to get tropical flake food. However, do not feed goldfish tropical food and do not feed tropical fish goldfish food. Keep the foods with the fish it says it feeds. Finally, just be patient. Sometimes you have to go through a few bad fish to get the good ones. I hope this helps. Let me know if you need anything else.