I don't know for sure and am just talkin out loud here. I have a hairy mushroom just like that for about a year now and hve not seen it split. It keeps getting larger but that's all. If I were to imagine it to split, my guess would be like other mushrooms where part of the foot splits from the base and starys growing another shroom
never seen that before..
if it were too much/too little light, or too much/too little flow, he would just walk to a better spot. so, i wouldnt think thats the problem..
nutrient problem maybe?
i think now that we talked about it, it is probably because someone glued the mushroom. and its trying to move.
it will pull itself off and heal or split
Ive got a bunch ive had this happen bunch of times first was getting ready to split and second was when my lights blew it wss pretty much lightless for 2 weeks and probaly wss missing the light and 3rd to much flow on it..all recovered from fixing the light and the flow
Don't worry too much about it lol your going to hate hairy mushrooms one day, they sting everything, I wish mine would decide to die... but if yours goes I'll hook you up with a couple replacements, my treat