Check it works
before you buy.

Q: How is sufficient volume determined?

Two checks: a stocking load in litres (each species takes up a volume per individual, summed and compared to your tank), and a minimum tank volume per species — if a species needs a bigger tank than yours, it's flagged with the required litres.

Q: Does it work for saltwater and reef?

Yes. The same engine handles freshwater, planted, reef, brackish and pond. Depending on the species present, it surfaces salinity for marine, GH for freshwater, and so on.

Q: Is planning a paid feature?

No, it's free. The Free plan lets you plan one aquarium; the Premium plan unlocks unlimited aquariums to plan your whole fishroom.

The biggest mistake in the hobby: buy first, check later. AquaTender flips the order. Build your future stock and see straight away the parameter compatibility and whether the volume will be enough.

Plan my tank for free What it checks

Before spending a euro · Before putting a fish at risk

Stocking & compatibilitycommunity · 120 L

12× Paracheirodon innesi 6× Corydoras panda 1× Pterophyllum scalare

Stocking68%

Temperature — common range 24–26 °C
pH — common range 6.5–7.0
Volume — Pterophyllum scalare: tank too small (min. 150 L)

Parameter compatibility

Species that share the same water

Every species tolerates a range of temperature, pH, hardness and salinity. AquaTender intersects those ranges for your stock and shows the common range — the target to aim for. If two species simply can't live together, it names them.

Compatibility here means water parameters (temperature, pH, KH, GH, salinity): the verifiable foundation, the one that puts a fish at risk when you get it wrong.

5 parameters intersected — temperature, pH, KH, GH and salinity, depending on the species you pick.
The common range shown — e.g. "temperature 24–26 °C": you know exactly what water to aim for.
Conflicts named — when there's no common range, the species involved are identified, not just a vague "warning".

Recommended common rangepresent livestock

Temperature — 24–26 °C
pH — 6.5–7.0
KH — 4–6 dKH
GH — no common range: Neocaridina and Tanganyika

Enough volume?

Neither overstocked nor too small

A live stocking gauge: each species takes up a volume, summed and compared to yours. It turns orange, then red, when you push too far.

And a separate check: if a species needs a bigger tank than yours, it's flagged with the minimum volume required — before you buy, not after.

Stocking in litres — a clear percentage that adjusts as you change quantities.
"Tank too small for X" — with the minimum required (e.g. "needs at least 150 L").
Try combinations — adjust species and quantities until everything turns green.

Stocking180 L

Volume used112%

Overstocked — remove a few individuals
Pterophyllum scalare — needs at least 150 L

The planning mode

A "work-in-progress" tank before water goes in

Mark your tank "Planning": the advice turns prescriptive — the warnings help you design it. Once the tank is up and running, the same diagnosis appears, but in an informational tone: the app guides you, it doesn't tell you off.

No separate shopping list to keep: your planned stock becomes your livestock the day you start the tank.

Freshwater, planted, reef, brackish, pond — one engine, the whole catalogue.
Volume estimated from dimensions — L × W × H, if you don't know it.
No nasty surprises — you decide calmly, the list is ready for the shop.

Tank status📐 planning

1× Betta splendens 8× Neocaridina davidi

Stocking34%

All compatible — ready for the shop

Frequently asked

What people often ask

What exactly does the compatibility check cover?

Water parameters: temperature, pH, KH, GH and salinity. AquaTender intersects the ranges each species tolerates, shows the common range and names the species that can't share the same water.

How is sufficient volume determined?

Two checks: a stocking load in litres (each species takes up a volume per individual, summed and compared to your tank) and a minimum tank volume per species — if a species needs a bigger tank than yours, it's flagged with the required litres.

Does it work for saltwater and reef?

Yes. The same engine handles freshwater, planted, reef, brackish and pond. Depending on the species present, it surfaces salinity for marine, GH for freshwater, and so on.

Is planning a paid feature?

No, it's free. The Free plan lets you plan one aquarium; the Premium plan unlocks unlimited aquariums to plan your whole fishroom.

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