Poor Little Princess

I remember just a handful of months ago Ryan and I were having a power stuggle over who would take down the Christmas tree. I put it up and decorated it, and I was happy to take all the decorations off it and box up all the Christmas stuff from the rest of the house, but I really wanted him to disassemble and put away the stupid tree. For some reason, he found this unreasonable, and the struggle went on until he finally lost. He wanted to go to Dallas for the weekend with his nerd buddies, and I wanted the tree taken down, so we compromised. He took the tree down after he got home from Dallas, and all was well.
Well, here I am some months later, and I'm looking for another bargaining chip. With the tree, life would have gone on even if we'd have butted heads all year long over it. It would have been annoying and in the way, but everything would be essentially the same. This time around, however, a life is at stake, so I need to find a way to end the stalemate. I'll tell you what's going on, and maybe you can offer some advice (before Ryan reads this...).
Last year at Kylie's preschool, there was a class beta fish. At the beginning of the year the teacher let Kylie name it, and she called it Princess. Later Kylie decided she'd like a pet, so I decided a beta fish was about as much pet as this family could handle. I let her work toward earning one by cleaning her room and things like that. She was getting close, and the end of school was apporaching. One day I went in to her classroom to read to the class, and I was asked if we would like to take Princess home since she was a school fish and really couldn't stay there alone all summer. So, we saved Princess from summer school (or the toilet, probably), and Kylie had her beta fish. Feed once or twice a day, clean out the bowl every 2 weeks or when it starts to look bad, and that's basically it. We can handle this. I got through the first few cleanings with no drama, but it was unpleasant. There is a particular odor that develops in the fish bowl, and you really smell it as you dump it out. It's not so bad as long as you do it every 2 weeks, and as long as noone is dumping handfuls of fish food into the bowl. The last time I cleaned it out, we had let it go a few days too long, and Alex had dumped WAY too much food in there. Marination occurred, and it was smelly. I, being pregnant and a little icky anyway, wretched the whole time I cleaned Princess's little house, and I declared it Ryan's job from then on. He wasn't happy about it, but he gave it a couple weeks and went to clean it out. That would have been fine if we hadn't had a couple friends visit briefly who wanted badly to feed the fish. One 3 year old boy came over, and I ended up scooping layers of fish food from the top of the bowl, but there was no way I could get it all out. Ryan proceeded to clean it out about 2 days later, and he swore he wouldn't be doing it again. He said that even for him the smell was too much. I promised him that it wouldn't be that bad if the kids would stop feeding her so much and letting their friends feed her. Since then I've been the resident fish feeder, and the bowl stayed much much cleaner much much longer, but here we are. The fish bowl now desperately needs to be cleaned out, and both of us are adamant that we're not doing it. I tell him I can't because I'll throw up, and he is telling me the same thing. I think I'm on stronger footing here, but he can be pretty stubborn. I really don't want the fish to die (though, admittedly, that would make things simpler), but I really don't want to be the one to fold here. I've thought about asking Kylie's kindergarten teacher if they'd like a classroom pet, but Ryan said that wouldnt' be right since it's kind of Alex's fish too. Any thoughts? Oh, or volunteers?