About
Every other aquarium game draws the fish. Reefline simulates the water they live in. Ammonia becomes nitrite and nitrite becomes nitrate, through two separate colonies of bacteria that grow at different speeds, which is why the nitrite spike always lags the ammonia spike and outlasts it. Dissolved oxygen falls as the water warms and every animal in it needs more. pH is set by carbonate hardness against dissolved carbon dioxide, and the carbonate is quietly eaten by the very nitrification keeping the tank alive, so a soft water tank that is never buffered will crash its own pH and stall the colony that was doing the work. Feed too much and the uneaten food rots into ammonia, because that is what uneaten food does. The app shows the number that decides everything and that no other aquarium app shows: the toxic NH3 fraction of the ammonia, which climbs steeply with pH, so the same two milligrams per litre is a nuisance at pH 6.6 and lethal at pH 8.2. Twenty four fish and invertebrate species each carry their own temperature, pH and hardness windows, adult size, minimum volume, shoal minimum and temperament, and compatibility is computed from four questions rather than read off a list: can one swallow the other, will one shred the other's fins, will one refuse to share the space, and can they both live in the same water. Body depth decides predation, not length, which is why an angelfish takes a slim neon tetra and leaves a deeper bodied rasbora of the same size alone. Twelve tanks run from a fishless cycle through a fish in rescue, an overstocked starter tank, a planted tank, a filter somebody rinsed under the tap, a buffer that has run out, a summer heatwave, a shop list of incompatible fish, soft water species in hard tap water, a twenty litre nano, a nano reef from day one and an established reef spending alkalinity faster than it goes in. Nothing in the model is random: when an animal dies you get a post mortem naming the parameter, the reading it reached, the hour it left its window and how long it stayed out. Reefline is bought once. There is no advertising, no currency, no energy timer and nothing further to buy, and it works with no connection at all.
Features
- A real nitrogen cycle: two bacterial colonies growing at different speeds on a fixed clock
- The toxic NH3 fraction shown beside total ammonia, because pH decides which one matters
- Dissolved oxygen against temperature and salinity, and pH from carbonate hardness and CO2
- 24 species with their own parameter windows, adult size, shoal minimum and temperament
- Compatibility computed from rules, with body depth deciding predation rather than length
- 12 scenario tanks plus a sandbox, every one certified solvable by a reference aquarist
- A post mortem on every loss: the parameter, the reading, the hour and the duration
- Bought once, works offline, no account, no advertising, nothing further to buy