Looking very nice OP. Are you adding any nutes, camg or sweeteners to the water? This is appealing to me since I love fish, I have a 37G fresh water planted tank for my daughter and a 75G reef tank and I enjoy growing my own medical so putting the 2 together will be fun.
everything is pretty much the same as hydro. feed as you normally would, any kind of nutes or supplements. no need for bennies, no h2o2 as that would kill all the good stuff. and you don't feed often, because you never flush. i feed to 1000ppm, then wait until it's down to 500ppm before i feed again.
you don't need to deliberately add nitrogen, but if it happens to be in your micro or calmag, i don't think that's a big deal. my fish food only contains about 1% phosphorus, which never proved to be enough during flowering without bottled nutes. if you're into all organic, check out vermiponics.
the only thing that gets depleted often is sulfur. i think it's slowly gassing off. i don't think it's unique to aquaponics, it's just that hydro growers never keep their solution around long enough for this to happen. you never flush with aquaponics, so the gassing off effect (if sulfur does, indeed, gas off) is noticeable over time. i now add a tablespoon of epsom salt to my 100gallon system every other week. if it's not gassing off, then my plants must just be sulfur-hungry.
what size of a system are you thinking of building?