When you do massive changes very often , does that disrupt the beneficial bacteria enviroment in the tank in any way ?
No all the BB is in the filter's and on the decoration's. If there is anything of a noticable change it will be your O2 which I compensate for with over airation.
I normally do 30 % every 10 days roughly. It can vary from 1 week to 2 weeks depending on my personal schedule. I will make it a point to do them weekly once the fish get bigger.
This is good enough for your set up it should be the normal. When your ready you can if you like bump it up to 50% a week and then 50% 2x a week.
I'm not officially in the xingu grow out event but I just got a 2 inch wild Rio Meta orino the other day from Rapps. In a way I will be participating in the growout event from the sideline
I got my orino gorging himself on Hikari food sticks. Pellet training took just 2 days.
I do think now after my experience with Orino's they are the easiest to switch over.
As for this xingu contest....What if 1 of you ends up with a pair and start spawning some babies