I find it interesting that there is push back on terrestrial plant matter. What is detritus? Nothing more than rotten plant matter and fish poop and terrestrial animal poop. That rotten plant matter is aquatic plants and terrestrial plants. Logs are terrestrial for crying out loud but we feed those to our wood eating "plecos."
This hobby is all science. You have to be something of an ichthyologist when choosing fish species, a nutritionist when deciding on food to feed, veterinarian when treating disease, and chemist when testing water. My other hobby is riding a motorcycle because its simple, twist throttle and go.