Yea that's is what I've been doing. I had a few mushrooms and then last year I did a major re-aquascape which involved taking all the LR out, building columns and putting them back. The result was a mushroom explosion. I have mushrooms everywhere, covering many, many rocks. So many that I've had to pull out the LR that I can, boil it for 20 minutes, then scrub off the melting mushrooms. I smother the mushrooms with kalk on the rocks I can't remove (lower in the tank. I've got a long way to go but I have made a significant impact and maybe removed 20% so far. It's a long project and a nasty one and I'm taking my time.
Be careful to turn off any additional flow pumps when you do the Kalk pasting. My Tunzes just blast it off. The mushroom needs to be covered for quite a few hours to be killed. Haven't timed it but 12 hours seems to do the job.
For me it's green mushrooms. I think they are Actinodiscus sp.