Flies on Monstera

[Mubgrub]

Hi all, has anyone ever had a problem with black flies on a Monstera?  I have one in my bathroom, its quite happy but seems to be the source of a load of icky black flies (think they might be fruit flies but not sure) they hide behind the pot and in the compost.  I've tried squishing them but there's just too many....

Any ideas/experiences?

Mub

[Mubgrub]

[Rosa_Mundi]

Are they actually harming the plant, or just in the compost? If the latter, try replacing the top inch or two of compost with a JI-type compost and mulch thickly with gravel or sand/grit. They are currently living on the surface of the compost, encouraged by a moist, open soil.

[Mubgrub]

I think they are just in the compost, I'll try that, thankyou.  :)