my fishs eye is gone

Question
my fish lost its eye since my friend bought it for me.
i thought it was just lost because it was bumped by something and it fell off. When my sister brought a fish to my aquarium, her fish dies after a couple of days.Then i bought two fishes, too.The following day it died, but the fish that has only one eye is still alive. What is its sickness?

Answer
Hi Keziah,
I'm sorry to hear about your fish. Sometimes fish lose an eye from an injury, popeye (which is a sickness causes the entire eye to swell), or a genetic defect. Fortunately most fish who lose an eye can survive and live a reasonably normal life, just make sure they always get their fair share of food at feeding times, competing with other fish will be difficult for them. With the dying fish problem you should test your water for ammonia, nitrites and nitrates. Make sure these levels are as follows- Ammonia-0 Nitrites-0 Nitrates- 20 or less.

If your tank has been recently setup then it may be going through the cycling stage you can read about here-

http://www.firsttankguide.net/cycle.php

Check your water quality, as poor water conditions due to an uncycled or unhealthy tank are the number 1 cause to fish deaths. If the water parameters are out of the healthy range, then daily 50% water changes should be done to correct the problem. Make sure the replacement water is always equal to or just a bit warmer than your tank water, and never forget to use a good quality water conditioner such as Amquel+ or Prime.

I really hope this helps!
Happy holidays,
Karen~