Assume Willingness, Not Fish Knowledge
Your sitter is probably conscientious and completely inexperienced, and the instructions should honour both facts. Write them as if the reader has never fed a fish: name each food by its container and its shelf, not its type; say where in the tank the food goes; and explain the one idea everything hangs on — in fishkeeping, too little food is a shrug and too much is a slow disaster. A hungry fish for a week is fine. A tank fed double for a week is cloudy, fouling and heading for losses, and the sitter who understands that sentence will forgive your instructions their detail.
Portion Everything Before You Leave
Do not describe amounts — eliminate them. Portion each day's feeding for each tank into small labelled pots or a weekly pill organiser, one compartment per feed, so the sitter's whole job is to empty the right pot into the right tank. This single step removes the classic holiday catastrophe: the generous pinch, repeated daily by someone who cannot see the harm accumulating in the water. If a food cannot be pre-portioned — live food, or frozen food that must be thawed first — leave that food off the sitter's list entirely and let the fish go without it for the week; the varied diet resumes when you return.
Write the Schedule the Way the Week Actually Runs
Tape the schedule where the food lives and write it in days, not abstractions: which tanks are fed daily, which every other day, which get a fasting day, and roughly when — anchored to something in the sitter's routine, like 'with the morning visit', rather than a bare hour nobody will keep. If different fish in one tank eat differently — flakes at the surface for the tetras, a sinking wafer after lights-out for the corydoras — give each its own line with its own pot, because a sitter cannot improvise a two-stage feed from one combined instruction.
The Exceptions a Good Sitter Still Meets
Leave one short section for the situations that break the routine. Fry and juveniles may need their extra small feeds on days when the adults fast. A fish that has just been added, or one being watched after an illness, may be on different instructions — say so explicitly, tank by tank. Write the begging rule in plain words: fish rushing the glass are performing, not starving, and extra food given 'because they looked hungry' is the one mistake not to make. And cover the missed visit: if a day is skipped entirely, the answer is to feed normally next time, never to catch up with a double portion.
A Short List for When Something Looks Wrong
End with three or four if-then lines, not a manual. If the water looks cloudy, feed nothing that day and send you a photo. If a fish has died, the instruction is to note it and tell you; removing it with the net left beside the tank is welcome but optional — no water change, no chemicals from the cupboard, no rescues into buckets. If equipment sounds wrong or has stopped, check its plug once, then call. The list's job is not to make the sitter a fishkeeper; it is to make waiting for your answer feel like the correct move, because it is. Instructions written this way are exactly what KinsLe's Care Pass is for: it hands your sitter temporary, clear access to each tank's feeding routine and key details, so the week runs on your portions and your schedule — not on a stranger's guesswork.