While you wait for answers, we may have found some information which could help you.
Click here for Dual Button FlushingGrohe push button toilet attached to saniflow ?
Short burst of water entering cistern ?
Grohe 42181 toilet filler valve leaking?
Grohe seals 14.11.30 4 DAL?
The push button on my Grohe Adagio stopped flushing ?
Slow fill of toilet cistern?