Stronger Acid

Stronger Acid speeds up the acid damage-over-time from the Alchemist's potions. The acid ticks every 1.5 seconds instead of every 2 seconds and lasts 4.5 seconds instead of 4. The same improvement applies to acid pools if you crosspath into Acid Pool.

When to buy it

It is a $250 step toward Perishing Potions and the middle path. On its own it adds a little early damage: with all ticks landing, the acid can pop bloons down further than before, and the faster ticks chip bloons more quickly. In most early-game cases, though, Larger Potions does more for the same price.

If you are not planning to go down the middle path, skip it and take Larger Potions instead.

Is it worth it?

Only as a step toward Perishing Potions, Unstable Concoction or Transforming Tonic. As a standalone upgrade it is a small improvement.