The different organic waste should be tested, one by one, feeding them to the fish in small quantities and processing it before to have it edible by the fsh (maybe dedicate an old blender to pre-chew it).
Other direction would be to compost it and use them in an other beneficial way.
The solution of the compost tower in the middle of grow beds is a good one though it comes with other issues such as :
- potential increase in nitrates in the water (it will all depends on grow beds total volume)
- organic matter coming in the grow beds and potentially clogging it
An alternative solution would be to get a worms or a BSF-larvae composting bin that would produce compost for your other grow beds (the traditional ones, not the aquaponics ones) then find a way to gather the worms or BSF larvae to feed them to the fish.
Also, for the non-organic food waste (left over of meat, eggs, bread,...) I wonder whether it would be suitable to feed the fish too (given it would be "pre-chewed" too), tilapias and catfish are omnivorous, they can eat meat (what about the cooked one?). Those won't be OK for composting.