I have a monte carlo carpet in my 20 gallon tank and I've let it go to long without trimming. Its more of a mat now but its got to be 3-4 inches thick. Can i cut into the mat without killing it or should i just focus on maintaining it ?
First of all, you have a clean tank sir, nice work!
Yes you can trim Monte Carlo, in fact you should trim it regularly. I also often poke hole in the carpet with this specie, it prevents it from shooting up. The reason is that Monte Carlo tend to grow really thick in a hi-tech environnement, this leads to air pouches forming underneath the carpet. Up to a point it can push roots out of the soil, can be annoying. And yes you can also cut in the mat if you want to remove chunks.
I've been trimming mine every 2 weeks to keep it about 1/2 inch. Recently I hacked it down to a quarter inch because it's a mess trimming so often. It really didn't like that as much as it's been a week and hasn't had the growth it usually had.
If it was me I would trim it a little every week till it's down to the height you want.
It is a mess to trim, i've done some basic trimming but clearly no where near enough. Will try to take an inch off maybe at first and see how it reacts, i figure if i cut into the mat I may just be able to trim it off in one piece. I actually have a lot of dragon stone in the tank which it completely overran.