If in the correct size pot for your set-up you'll see no yield difference from watering every day to every other day, first hand. If the plants are wilted feeding every other day then use a bigger pot. This however depends on your root/canopy temps and root establishment being optimal so that the top inch and outer edges of the pot dry enough to make the area uninhabitable to gnats, yet the inner core of the pot is still wet enough to support the plant with no wilt. You'll waste a little coco this way but it's a cheap and hassle free solution that requires one less product and gives you a lot more free time (the true upside -.^).
On the flip side if you use a pot that is too big for your root establishment (or low temps) the plants won't take up enough of the water volume between feeding's, the outer/top inch of coco will stay moist for too long and will then support gnats.
If you use monthly top dress or teas w/e you may see a slight foot hold in gnats but they won't last long with this method, a week tops.
Air pots are a blessing when you get this right, since they allow most of the outer edges to dry properly giving the gnats nowhere to hide. If you get it wrong though, it's a bit of a double sided sword, they then have full access.
It's a vague guess but say you were using a 5L pot and feeding every day, you'd probably have to step up to around an 8L pot to get away with every other day feeding. A 10L pot every day would require a 15L pot for every other day. Really just a loose guide, and temps etc also play a role in it, you have a good chance to get away doing it with current sized pots, it's something you'd have to play around with, but won't regret when you get it.