Overview
Aquarium is a smart wallet feature that lets you pay network fees with any token you already hold, so you don't have to keep a separate stash of ADA just to send things. Think of it like paying highway tolls with the currency in your pocket instead of being forced to find exact change. Pick what you want to send, pick the token you want to spend, and the app sorts out the rest1.
It's built by FluidTokens, a team behind a family of Cardano apps for lending, renting, and earning yield. The idea of paying fees in any token comes from a Cardano research paper by Input Output Group, the network's original engineering company, and Aquarium is the live, everyday version of that idea2.
Key Features
- Send a transaction without holding ADA. Pick the token you want to spend, and Aquarium handles the ADA part of the fee in the background. Helpful for new users who don't want to buy ADA before their first action1.
- Earn a reward by helping cover other people's fees. Park some ADA in a "fee tank" and it quietly pays for other users' transactions. In return, you collect their tokens, turning idle ADA into a small ongoing income3.
- Schedule a payment for later. Set up a transaction to go out once at a future time or to repeat on a schedule. A group of independent operators races to carry it out at the right moment3.
- Independently audited code. The on-chain code that runs Aquarium was reviewed by Anastasia Labs, a Cardano security firm, and the full report is public4.
- Open source and inspectable. The code that runs fee tanks, scheduled payments, and operator rules is published openly in the FluidTokens GitHub organisation so anyone can review it3.
What to Expect
The Aquarium homepage shows three cards: pay a fee in any token, set up a fee tank, or schedule a payment. Each one starts by connecting a Cardano wallet, a self-custody app that holds your keys. The "Try Babel Fees" card is the friendliest place to start: pick what to send, pick which token covers the fee, and the form fills in the rest. The other two cards are for people who want to put ADA to work or automate something.
For builders, Aquarium plugs into other payments and accounting tools through a standard integration, but the integration details live behind the FluidTokens Discord rather than a public developer page1. Support, questions, and partnership requests all run through the parent FluidTokens community channels; there is no Aquarium-only social presence. The full documentation sits at docs.fluidtokens.com, where Aquarium lives next to FluidTokens' other Cardano products5.
