For plant, In the absence of soil it is difficult to absorb the nutrients and in aquaponics water is continuously recirculating so it is more difficult to absorb the nutrients by roots. So in that condition condition the role of foliar spray is very important, plant can easily absorb nutrients through stomata of the leave.

Through foliar spray we can provide the deficient minerals and can manage the nutrients balance. It can improve the growth and yield.

So I think it is necessary to give nutrients through foliar spray in order to manage the nutrients balance for the plant nutrition.

Thank you Dr Naresh Raj Keer for expressing your views.

Your welcome 😊 @Harsha Haridas

I don't think this is recommended