The bulk of what you are seeing is turbidity in the water ( river tank ) with a lot of tannins… but admit on this tank the glass has also been a challenge...
I still have 2-30 gallon long tanks in my "built in" set up, that I’ve not refilled yet… along that line of thought... a lot of these fish are river fish... will they effectively reproduce in a tank where the only water movement comes from a sponge filter??? I get that you wouldn't want to suck up the eggs or fry, but if there is no water movement, will the fish still spawn??? may have to watch that, & have plenty of sponge filtering, & then turn off the major water moving filters when the pair are in the mood???
At this point the tanks running are just display tanks… and I’m happy with that, and how well they are doing right now… but, I’m too busy to even set up another tank right now…. I’ll be retiring in a couple years, and hopefully I’ll have a couple fish up to the task, when I have a little more time… between working full time plus, raising farm animals ( raising our own food ) and trying to keep up with everything… I just don’t have the time to dedicate yet…
Thanks for acknowledging that I have unusual fish, and that they seem to be doing well… anything worth doing, I like to try to do right...