Aside from fungus gnats, Audrey may also be dealing with some bacterial and/or fungal disease. I say that because even new growth, stem and leaves appear to be affected. If that's the case, my suggestion would be to quarantine Audrey, wash the roots, scrub the pot very well, then re-plant it in fresh, new potting mix. And, of course, avoid over-watering it.

Whoever suggested Amber should destroy root lipid membranes (by watering with a solution of dishsoap and water) to kill fungus gnats, should have their license to give advice about plants revoked.

Old post, so I don't know if you still have the plant or not, but the necrotic leaf tips and margins are symptomatic of a compromised root system, more specifically, an inability of the root system to efficiently move water to the plant's most distal parts (leaf tips/margins). This is a direct result of the volume of oxygen (in the root zone) being insufficient to drive normal root function. In most cases, the reason for a dearth of oxygen in the rootzone is resultant of a chronic excess of water in the grow medium, but however unlikely, it's still possible soil compaction alone, w/o the specter of over-watering, could be the root cause (no pun).

Neither is there anything in the images to suggest bacterial issues or one of the fungaluglies are in play.

Al

Did you figure this out? im having th

e exact issue!

If you're seeing the same symptoms in various states of severity on several leaves, there is very likely an issue affecting root health/ function; however, if involvement doesn't extend beyond the single leaf, I would say that it's not likely anything to be concerned about. The reason I'm suggesting this is, when I enlarge the image, it appears that the leaf suffered a mechanical injury, a crack, probably due to the leaf being folded at some point in time. At the center of the lesion, you can see lighter tissue that forms an obtuse angle of about 135*, with the bottom leg of the crack extending beyond the boundary of the lesion. If the crack I'm talking about were clock hands, the top hand would be at about 1 o'clock and the bottom hand at about 5 o'clock.

Let us know if more than 1 leaf is involved. If it is, let us know how you determine when it's time to water and how you actually go about watering. The devil is very often in the details, but there are no details.

Al