How to Get Mutated Fish
A mutation multiplies what a fish sells for — and what it earns in your aquarium. There are four: Gold ×2, Diamond ×5, Venom ×10, Hole ×20. The most valuable, Hole ×20, spawns rarely — unless you hunt during its weather window.
Guide last updated:
The spawn rules
- Fish spawn with mutations already applied — Gold and Diamond in any pool, Venom and Hole rarely.
- You can't mutate a fish after catching it; farming means catching new spawns.
- A fish carries at most one mutation — no stacking.
- World fish despawn on a timer, so grab mutated spawns on sight.
- You'll recognize them: Gold is metallic gold, Diamond is cyan, Venom is neon green, Hole is very dark — with the mutation name shown above the fish name.
Watch the weather — that's the whole trick
Poison weather → Venom
During Poison weather, Venom fish spawn chance rises by roughly +10% for about 4 minutes. When it hits, stop draining and sweep spawn points for the window.
Black Hole weather → Hole
Same deal for the ×20 Hole mutation — roughly +10% spawn chance for about 4 minutes. One guide reports it fires about twice an hour, but treat that as a tendency, not a schedule.
Weather only affects newly spawning fish — a fish already swimming stays whatever it was.
What they're worth
Sell value = base value × mutation multiplier, and the same multiplied rate applies in the aquarium. Run your fish through the Fish Value Calculator or compare all four at once with the Mutation Calculator. One honesty note: these multipliers are player-measured — three guides agree on them, but there's no official stat sheet.
FAQ
Can you make a fish mutate after catching it?
No. Fish spawn pre-mutated — the mutation is fixed at spawn, so a normal fish can never become Gold or Hole later. Farming mutations means catching new spawns, ideally during weather windows.
What are the odds of a mutation?
Not published. Gold and Diamond are described as relatively common natural spawns; Venom and Hole are rare. During Poison/Black Hole weather the boosted mutations get roughly +10% spawn chance for about 4 minutes.
Should I sell mutated fish or display them?
Display them. The mutation multiplier applies to aquarium earnings too, so a Hole (×20) fish in your aquarium pays its multiplied rate every minute — community guides call mutated fish the backbone of aquarium income.
Sources
- allthings.how — +1 Drain Water Per Click mutationsthird-partyhttps://allthings.how/1-drain-water-per-click-mutations/(accessed August 28, 2026)Mutation multipliers, weather windows (+10% spawn, ~4 minutes).
- TechWiser — Mutations in +1 Drain Water Per Clickthird-partyhttps://techwiser.com/mutations-1-drain-water-per-click/(accessed August 28, 2026)Gold ×2, Diamond ×5, Venom ×10, Hole ×20 (player-measured).
- Nerd's Chalk — best fish mutations in +1 Drain Water Per Clickthird-partyhttps://nerdschalk.com/best-fish-mutations-drain-water-per-click/(accessed August 28, 2026)Confirms mutation multipliers and weather effects; caveats values are player measurements.
- Sportskeeda — +1 Drain Water Per Click beginner guidethird-partyhttps://www.sportskeeda.com/roblox-news/1-drain-water-per-click-a-beginner-s-guide(accessed August 28, 2026)Core loop, currencies, pumps > pets precedence, aquarium income, auras, upgrade order. Published August 22, 2026. Page blocked direct fetch; captured via search snapshots.
Values on this page are only as reliable as their sources. See our methodology for how data is collected and verified.