My system completed its cycling a little over 2 months ago. I am raising a nice amount of lettuce and not much else. I have 25 tilapia in a 180 gal tank. The fish are 2.5 to 3 inches in length. They eat like pigs.
The grow bed is 12 sq feet under 600w Metal Halide lighting run for 18 hours/day.
I have just had an infestation of aphids and white fly and am just now regaining control. While doing this, I pulled my tomato plants and a very healthy canteloupe that produced nothing but green.
The lettuce is very productive and keeps my wife and myself in salad once per day.
My question is this: The fish seem healthy, the plants are growing nicely, the nitrate is at 160+.
What is needed if anything to be done?