Bichirs eat using inertial suction meaning that when they go to take a bite, they create a vacuum and suck up the food and the risk eating the gravel and getting impacted
Just go back to sand and vacuum sand like you would with gravel and shouldn't smell. I personally never experienced sand smelling in any of my aquariums.
Ok. But I would like to scape the sides with river rock, and various plants, and scape the river rock in a way where Sparky can slither through them while he is young. Then put a driftwood piece in the middle. I would put in large fake plants while the plants would grow to create a beutiful tank . I was thinking really white sand. Any cheap ideas? My last sand was pool filter sand. I think white sand woul look better. Where can I get it where it is relatively chep?
Honestly as long as there is no way that the bichir could swallow it (now also keep in mind full grown bichir, I know yours is a baby presently) but just make sure that they are too big to get eaten by accident
Imo gravel and larger pebbles trap more junk then sand. Also not recommended for the reasons listed above with bichirs. I use pool filter sand and it's pretty white. Really white sand can make your fish wash out also. Like
tlindsey said you can easily vacuum sand it just takes some patients, the the junk tends to sit on top of it more so then gravel. River rocks will look and work ok as long as a grown bichirs can not swallow it. I doubt you will get the actions from the bichir you expect concerning his interactions with said stones.