Blair, I know you keep/kept your rotkiel in a semi planted tank fairly well... came home today to find bite marks out of my favourite hygro. Any tips on keeping these guys from eating everything and anything green?
I kept my rotkiels with Java Fern & Anubias - which are both supposedly bitter and not enticing to eat... I also kept a very fast growing floating plant called Pennywort - if they ate it you'd never notice! So basically I guess my advice is try to find plants they don't like, or get plants that grow fast enough they can't keep up!
So from my research it seems they obv like a good old dig at spawning time so use eggcrate on the base of the tank and secure plants into it so they root under the eggcrate. Find plants they dont llike to eat (there is a list here from someone http://www.virtualseeds.com/tankmates.html) and feed them on other veggies to keep them happy as suggested above.
I like te idea of keeping a fast growing floating plant that they like to keep them away from other stuff as mentioned above. I did speak to a guy who created a ball of trimmed plants and dropped it into the tank for the Sevs to graze on. He said it worked for him!
Good luck with it, research of their biotope suggests they like to be in and amongst plants, so anything yo can do to give them their natural habitat must be a winner.