Why my aquaponic tomatoes leaves dying?

[Fawzi Fadil]

I would love for any one help me on this? Why my tomatoes leaves Turing brown. Fish is healthy. Water is circulating fine

[Fawzi Fadil]

Thank you so much. Maybe as you said: too much wet. Working out a timer maybe will fix it. Many thanks

[Michelle Tonkinson]

Low iron?  Add chelated iron.  Too wet?  Slow timer to fill less often.  Too cold?  Tomatoes like it hot.