Bug or insect problem...Please help.

Hello, about a week ago I noticed that some of the leaves at the very bottom of the plant were missing some really small pieces but didn't really think that it could be something serious. However, today I had a better inspection and because my growing room is quite narrow, I haven't noticed that one of the plants is seriously infected by something.

As I inspected all my plants very well, I found that the most of them have the same problem but apparently in much earlier stage. The leaves are literally like eaten by something, as you can see in the photos. Please tell me what could be this and how can I heal the plants. Appreciate your time and advises.

Are the newly affected leaves slightly shiny?

If so you have Thrips.

Mix soap and water and spray the plant. I have actually hand washed every leaf of a plant and it didn't hurt it.

If that doesn't work, soap+99% rubbing alcohol. Spray on the leaves, leave for a while, wash off the leaves.

Firstly, thanks for the reply. The newly affected leaves don't seem shiny to me... just normal as the rest of the leaves. However, I checked what the Thrips is and the damage really look like the one they make. I will try the soapy water, but is there any chance I can do some harm to the plant if the water is too soapy or if the soap is stronger or something like this?

Use dish soap, it can't hurt your plant.

Nevermind........

I found the problem! There are small green caterpillars eating my plants. I sprayed them with "Deep impact plant care-Deep Clean" and will update you what will happen.

Ahh caterpillers... grow in a soiless medium they hate that