Need help diagnosing and treating. All fish eating normal except 1. 4 fish have hazy eyes and skin looks hazy, 7 seem fine. May have white specs or maybe sand. Swimming normally, not rubbing on anything. All fish are in display tank. Have not added any new fish for over 6 months. Most of them I have has for 9+ years.
That does not look like velvet at all. I cannot diagnose velvet without a clear video to check the breathing rate. However, I can see discrete spots which you would NOT see with velvet. With velvet, the fish breathes fast and stops feeding. This is either ich or flukes, or both. The cloudy eyes point to flukes, but the lack of scratching points to ich.
What fish is not eating normally?
Can you post a video of that fish, plus one of the tangs, under white light?
How long have they been showing symptoms?
Do you have a treatment tank available?