What i mean is every fish is different and it may work out for him and everything will be fine with all of them in the tank until he gets a new tank and if the aro does happen to die its not like its a $1000+ fish and he could purchase a new one and do something different this time. A huge part of this hobby is trying and seeing what works and what doesn't. Whine, complain, call peta, throw fish scales and blood on me idc but you never really know until you try. Best of luck with your project