There is a TON needed to be done before anything can be declared as scientifically proven.. Its a great start to base an hypothesis off of, but for the time being that’s all it is. Sure they had a control, but like Allen said in the other thread there are just too many contributing variables that need to be in check. All science needs to start somewhere and this could very well prove to be true after more studies are done so really if carbon is not that big of a role in your system it couldn’t hurt to remove it, or never use it in the first place (I don’t). To give it some merit all that needs to be done are some legitimate controlled experiments in which other factors (such as liverock and over crowding) are not present, think QT tanks. Personally, I wouldnt run carbon if I had a decent fish population that could develop HLLE though, just to be on the safe side with all the investment in money and care