Inches per gallon rule is bunk, I don't use it at all. I do my initial stocking plan with AqAdvisor combined with researching the needs of the fish I have planned. While stocking the tank over several months, I keep a close eye on the nitrate tests as well as the behaviors of the fish in the tank. As long as nitrates look fine and the fish aren't having any territorial issues, I continue stocking according to my initial plan.
That said, It's pretty rare for me to actually follow my initial plan 100 percent. I often will stop early if I can't visualize the niche that a new fish would fit into amongst the current inhabitants because I don't want to risk causing territorial issues. On the cases where I do stick to the initial plan and stock it fully by that, I can't think of any times when I sat back afterwards and felt like I had under-stocked and was missing something.
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