Why, just why? There is literally no useful application for this beyond those who want the novelty of keeping fish together that should not be kept together. I wonder how the use of sugars to mimic the mineral content of salt water affects issues like water quality. Additionally, regardless of how well these things work in the sort term, I really can't see the poor fish not suffering some sort of osmoregulatory stress from being kept in these conditions long term. Who knows how being forced to live in these conditions would affect their overall lifespan and quality of life. I wouldn't be surprised if both fresh and salt water fish are more prone to disease and sickness in these set ups. Beyond that, what exactly do we have to gain from being able to do this in the first place? The people who wasted their time on creating this product should have been working on something more societally important instead of creating something that has no purpose aside from allowing them to profit from the uneducated and unethical.