I lived completely off grid in a tropical forest for nearly 10 years, and had several different iterations of hydro/aero/aqua ponics systems inoperation for large periods of that time. In my location the concept of 'indoors' was largely ideological; the mosquito netting over each bed was the least buggy location, but nowhere was bug free.
The best solution to controlling insect damage to domesticated plants was a combination of rigorous mechanical control (squishing them) and periodic application of a combination of neem oil or melaleuca oil, chili powder, and a strong soap (Dr Bronners was my choice just by availability) all in suspension with rainwater.
The oils are pretty readily available, and can be produced in small quantities on site in some locations. Otherwise a soy+garlic oil with a little chili capsicum will also stand in for neem oil, but without as much fungal inhabitant effect in my experience.
Start lean in the soap:oil:water ratios, a very little bit can be effective for a lot of vegetation when applied with the finest mister tip on a hand pumped sprayer.
Don't expect dead bugs all over the floor, using non-toxic formulas like this are often most effective at interrupting the reproductive cycles and most effectiveness will be in reductions of recurrent hatches.
One careful note; the oil/soap/capsaicin blend is pretty effective on even beneficial insects, and if you can encourage a healthy spider, mantis, ladybug, etc population most of the critter control can be left to them.
A few insects i found have some resistance to this oil soap mist, in particular very waxy tiny aphids and mites and a few very invasive tiny fire ants.
These succumbed to periodic spray with a kaolin and diotomaceous earth powder, applied dry to plants not likely to get direct rainfall and sprayed as a very fine slurry to uncovered plants with enough time to adhere and mostly dry before the afternoon rain washed it off.
The two powders interfere with respiration and mechanical aspects of arthropod exoskeletons and if applied at the right time (egg laying/hatching intervals) will interrupt the target insect populations and help get it back into a controllable state for your hungry beneficial insects.
In some indoor garden spaces a useful tactic was putting my hens (chicken and guinea fowl) into the greenhouse some days at 'roost out' for a brief spell, beginning when I had noticed a few more cutworms in the squash bean and corn. For this to work the bugs have to be tasty chicken treats, and you need to have cooperative birds that don't tear into unbuggy fruit. It cost me a few hens at first, but the rest seemed to either not be inclined to damage fruit or maybe they learned ... they werent very smart so it must have just been luck. One thing is if the birds learn that it is a short opportunity in the early morning when they are very perky, then they get quick about getting through the plants in a hustle, because i was gonna 'shoo' them out after my coffee.
PS the oil soap didnt seem to have any effect on the bugs being palatable to the hens or to the hens themself, but in theory the kaolin+DE could lead to inhalation silicosis for humans and fowl so don't breathe the dust yourself in large doses or over long durations, and rinse any powdery residue down before allowing the birds inside.
But be aware, guinea fowl in particular appear to like to eat praying mantids... that was maybe the most expensive per unit treat i ever bought the hens.
Hope this helps. Can you tell I wish I was still farming in the tropics.
