New to forum and aquaponics basically. I have a system that is a 6ft x 2.5ft x 9 inch grow bed and a 300 gallon fish pond (200 gallons in it currently). I have had the plants in the grow bed for 3 weeks now and they are growing but in the last week seem to be yellowing. Im assuming a lack of nitrogen. I only have 15 goldfish in the tank as I didnt want to overload the system while the bacteria was building up. I jumped started it with bacteria from pet store bottle and stress zyme. Ammonia stays at 0-.2 on test constantly. I guess the real question here is how many fish would you suggest in tank from given info? In my mind the problem with the plants is a lack of fish to produce enough waste to convert into plant food. Also system is set up on time clock to flood 15 mins and off 45 mins and a diverter to a skippy filter dumping back into pond. Thanks in advance.