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Hydrex is a decentralized exchange (DEX) built on Base network where THEO can be bought, sold, and traded. Because Hydrex runs on Base rather than Autheo Mainnet, you’ll need THEO (or funds to buy THEO) available on Base network before you can trade.
If you already hold THEO on Autheo Mainnet — for example, validator rewards, staking rewards, or Node Sale tokens — bridge it to Base first. See Bridging THEO from Autheo Mainnet to Base.

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Requirements

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1. Get ETH on Base for gas

Every buy, sell, or trade on Hydrex requires ETH on Base network to pay gas. You can acquire it by:
  • Buying ETH (Base) directly on a CEX or DEX
  • Swapping into it using your wallet’s built-in swap feature (e.g. MetaMask Swap)
  • Bridging ETH from another network to Base via Base Bridge or a third-party cross-chain bridge (e.g. Superbridge, Brid.gg)

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2. Add THEO as a custom token on Base

The first time you interact with THEO on Base, add it as a custom token in your wallet. The steps below use MetaMask; the process is similar for other EVM wallets.
1

Select Base network

In your wallet, go to Tokens and select Base network.Selecting Base network in wallet tokens view
2

Open Manage tokens

Click the three-dot menu and choose Manage tokens.Manage tokens menu option
3

Add a custom token

Click Add a custom token.Add a custom token option
4

Enter the THEO contract address

Make sure the Network is set to Base, then enter the token contract address:
Click Add token.
Always verify this contract address against this page or docs.autheo.com directly before adding it or entering it into a swap. Never trust a contract address sent to you in a message or DM.
Entering the THEO token contract address on Base
5

Confirm THEO is visible

THEO now appears in your wallet’s token list for Base network.THEO token visible in wallet

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3. Connect to Hydrex

1

Go to Hydrex

Navigate to https://www.hydrex.fi/.Hydrex homepage
2

Connect your wallet

Click Connect.Connect button on HydrexChoose the wallet you want to use.Wallet selection modalAfter choosing the desired wallet (e.g. MetaMask), click Connect.Confirming wallet connectionYour wallet address is displayed once the connection succeeds.Wallet connected and address displayed
3

Open the swap interface

Click Trade, or go directly to hydrex.fi/swap.Hydrex trade and swap page

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4. Buy THEO

1

Choose the token to sell

In the Sell field, choose the token you want to use to buy THEO (e.g. USDC).Choosing the sell token
2

Choose THEO in the Buy field

In the Buy field, choose THEO. Verify the contract address by copying it (using the overlapping-squares copy icon) and checking it matches 0xebE516a20238F79DC20b07eaD6768e08891Ed309.Selecting THEO in the buy field and verifying the contract address
3

Confirm the trade

Enter the amount you want to buy, then confirm the transaction. This triggers a wallet pop-up for signing — approve it to complete the purchase.

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5. Sell or trade THEO

1

Choose THEO as the token to sell

In the Sell field, choose THEO.Choosing THEO in the sell field
2

Choose the token to buy

In the Buy field, choose the token you want to receive (e.g. USDC).Choosing the token to receive
3

Confirm the trade

Enter the amount you want to sell, then confirm the transaction. This triggers a wallet pop-up for signing — approve it to complete the trade.
Hydrex is an independent, third-party decentralized exchange built on Base and is not owned or operated by Autheo. Trading on Hydrex is subject to Hydrex’s own terms — review Hydrex’s Terms of Service before trading.