How Pool Depth Changes Treasury Swap Output

Pool depth determines how far a treasury swap’s execution price moves as the trade consumes liquidity. A pool quotes against its current asset balances, so the amount received depends on both the size of the treasury’s order and the liquidity available along its route. A displayed spot price is only the starting ratio; it does not promise that price for the full trade.

For a treasury team, the practical question is how much value the route can deliver after price impact and fees. A deeper pool usually absorbs a given order with less price movement. A shallow pool can make the same allocation materially more expensive, even when the quoted market price looks attractive. The route mechanics behind a thor swap are covered in more detail in the companion explainer; here the focus is how depth changes realized output.

How does pool depth change the amount received?

In a constant-product pool, the contract preserves the product of the two token balances as trades move those balances. If a treasury swaps token X for token Y, it adds X and removes Y. The larger the input compared with the pool’s reserves, the further the pool’s exchange ratio moves against the trade. This movement is price impact: the difference between the starting pool price and the average price paid across the order.

Pool depth is not simply the total value shown in a dashboard. The relevant reserves are the balances used by the swap mechanism for the specific route. A pool can have substantial total value and still offer limited depth on the side the trade needs, or have an imbalanced ratio that worsens execution in one direction. Check the asset balances and the precise route, not only a headline TVL figure.

On THORChain, Continuous Liquidity Pools connect assets through RUNE. A swap between two non-RUNE assets executes through both pools: first into RUNE, then from RUNE into the destination asset. Each leg changes its pool ratio and contributes to the final output. The weaker leg can dominate the route’s price impact, so assessing only the source pool gives an incomplete estimate.

Which costs should a treasury include in its estimate?

A treasury should compare net output after pool impact, protocol fees, and chain transaction costs. These are separate costs. In THORChain, the slip-based liquidity fee rises with the swap’s size relative to pool depth and is deducted during execution. The source-chain transaction has its own network fee, and the destination transfer can incur an outbound fee. An integrator may also charge an affiliate fee.

For a two-pool route, fees and price impact compound across the legs. A deep source pool does not cancel a shallow destination pool. Nor does a favorable spot ratio guarantee a favorable net quote after fees. Compare a route quote with the amount the treasury would receive after deductions, and record when the quote was obtained. Pool balances can change before execution as other swaps arrive.

For a large order, a single fast swap and a time-sliced swap make different trade-offs. THORChain’s Streaming Swaps divide one deposit into sequential sub-swaps. Smaller executions can reduce the impact of each trade and give arbitrageurs time to rebalance pools between them. That can improve the total output, but execution takes longer and pool conditions can change during the stream. A minimum-output price limit can constrain execution; if the stream cannot meet it, some or all of the inbound amount may be refunded.

• Measure the order against the reserves in each pool on its route.
• Compare net output after liquidity, inbound, outbound, and any affiliate fees.
• For a large order, compare immediate execution with streaming and account for the delay.
• Set a minimum output that reflects the treasury’s acceptable execution price.

When should a treasury split or delay a swap?

Splitting is useful when a large order is a substantial share of available depth and the treasury can tolerate slower execution. Streaming can reduce per-swap impact without requiring separate source-chain deposits for each piece. But it does not create liquidity: if depth stays shallow, later portions still face the same constraint, and market movement during execution may outweigh the benefit of smaller slices.

Waiting can make sense when the route’s depth is temporarily low or its pool price has moved away from external markets. Arbitrageurs trade against those gaps and can bring pool prices back toward external prices, but that process is not a guarantee of a better quote at a particular time. A treasury with a firm deadline may reasonably accept higher impact for faster settlement; one with flexible timing can compare execution windows and enforce a minimum output.

The useful comparison is the trade’s estimated net output across available routes and execution modes, measured against the treasury’s required amount and deadline. Confirmed mechanics include reserve-sensitive price impact, THORChain’s RUNE-linked route for swaps between non-RUNE assets, slip-based fees, and streaming execution. The final output for a particular treasury order remains unverified until the route, pool balances, fees, and execution conditions are known.