They eat off the bottom, and because they are pretty much blind (at least my Del was), they grab what they can. If you have gravel they may grab a bite of some by accident, then you have a problem on your hands (imagine a piece of gravel traveling through their tiny little system, and imagine what comes next)… i.e. it can lead to major complications with digestion, and your end result could be a dead Poly. Besides that, they spend most of their time on the bottom, and sand is easier on them. And yes, they do like to bury themselves and burrow and such; it’s one of their hunting techniques…
well I read somewhere else that bichirs do just fine even if its bare bottom or with substrates tanks. besides, bare bottom tanks are much easier to maintain.
Barebottom tankes are ok but I thought on this thread you are trying to find a more natural look. Correct me if im wrong. And sand especially PFS is just as easy as Barebottom to clean all the junk sits on top of it.
They eat off the bottom, and because they are pretty much blind (at least my Del was), they grab what they can. If you have gravel they may grab a bite of some by accident, then you have a problem on your hands (imagine a piece of gravel traveling through their tiny little system, and imagine what comes next) i.e. it can lead to major complications with digestion, and your end result could be a dead Poly. Besides that, they spend most of their time on the bottom, and sand is easier on them. And yes, they do like to bury themselves and burrow and such; its one of their hunting techniques
They may swallow substrate as they eat from the bottom. Gravel can block their digestive track. And they actually do borrow their heads into the sand.