Backyard Aquaponics
A place to discuss aquaponics

I finally have strawberries, but as soon as they turn red they look like the picture. Not sure if this is caused by dust mites or something else? But its ugly and I have not seen that before......

Looks like mold of some sort. I'd look into a fish-safe fungicide and spray the plants. I'd remove any infected fruit and parts asap too, chances are they aren't recoverable in any way.

Kinda looks like grey mold?

Try this link:

http://www.ncstrawberry.com/docs/MajorS ... s11-08.pdf

How are your temperatures and humidity?

Its definitely mould,in the pic the berries are hanging over the side of the bed,when there in the bed is the top of your media wet,damp or moist,if it is lower your water level to stop it,just a thought as this could give you your mould problem,any chance of improving air flow around the plants ? this will help as well.Here in north Thailand we have very high humidity and if the strawberries are touching the ground this happens,the growers here over come it by mounding the soil to raise the plants then mulching heavily with rice straw to keep the strawberries off the ground.