ewurm, don't try to breed your female again for another 2 weeks or so. no offense, i just didn't know if you knew that or not. she needs time to rest and produce fertile eggs. 
plants, gravel, any decor is a bad idea. bare-bottom tanks are best. i usually use half of a little styrofoam cup to make his nest in. that's all the fry have to hide in. the rest is free swimming space. i vote for leaving it open. fyi: i have about 8-10 fry surviving right now. i hope they keep doing well. i've never made it this far.ewurm said:OK, I cleared the plants and cleaned the tank, the plants were a bad idea, too messy. Should I get a plastic plant for them or leave the swimming space open? I will add the female again in a week.

yes. it pretty much floats by itself if you gently place it on the top of the water. what i usually do is take a smaller styrofoam cup and cut it in half. it leaves a "dome" sort of for him to make his nest in. technically, it would be the same idea if you were to use floating breeding grass. it just gives a secure place for the bubbles. i hope that helps.ewurm said:Do you leave the styrofoam to float?
That is a great videocheck this video out ewurm. these are my two a few minutes ago. don't mind the voice in the background. my mom is nuts and she was on the phone!
Click here to watch bettas-breeding