Small system hickup and lighting change.

I noticed one dead fish the other day and really didn't think much of it. I mean I added 50 fish and this is the first one to die. I figured things were ok but still checked the water readings and things seamed fine. Honestly the levels haven't changed much since adding the fish. PH may have gone up just slightly. System is still not finished cycling yet though. I checked again yesterday and found another dead fish and a few moving slowly. I also noticed now the water getting cloudy. I think I might have been overfeeding. I am going to cut back for a few days and see what happens. I also need to add water to the system even with the cool temps in the basement I am still losing a bit to evaporation. I have noticed a few gnats or maybe fruit flies around the plants the last couple days. I won't use pesticides in this system so hopefully a few stick fly traps will work. Keep you guys updated on the status of the fish with an update this coming weekend.
On a side not I found a large 65 watt CFL bulb that I am going to work into the system lighting. It puts out 4400 lumens and light temp 2700k. It is quite bright and I think it will help with peppers I am going to add to the system this weekend. I changed out some of the bulbs in the neon fixtures as well. I am now using 1 bulb light temp 6500k and 1 bulb 3300k in each fixture. The plants really seem to like this now.