Can Discus Live With Molly?
Maybe, with caveats -- discus and mollies tolerate the same temperature, but discus are slow and docile while mollies are active and may cause stress.
Why
- Discus fish grow to 8 to 10 inches and require pristine, warm water at 82-86F with low current.
- Mollies reach 4 to 5 inches and are active swimmers that may stress slow-moving discus with their energy.
- Both species meet at 82F and pH 7.0, the only overlap point in their ranges, but discus prefer warmer and softer water overall.
- A 55-gallon or larger gives discus enough room to move without colliding with molly traffic patterns.
What could go wrong
Mollies may outcompete discus for food and stress them with constant movement, leading to discus failing to thrive.
Gear for a shared tank
Sized for the 55 gallon minimum this pairing needs. Affiliate links — we earn a small commission if you buy through them.
Fluval 307 Performance Canister Filter
Oversized filtration is what lets you stock two species together without water quality crashing. Rated for a tank slightly larger than the 55 gallon minimum.
Eheim Jager 300W Thermostat Heater
Holds a steady temperature inside the 82-82°F window both species need.
API Freshwater Master Test Kit
Keep ammonia, nitrite, and nitrate in check. Two-species tanks have more bioload and less margin for error than single-species setups.
Better pairings to consider
Discus do best with quiet tankmates like cardinal tetras or rummy-nose tetras; mollies do well with platies or swordtails.
Related compatibility questions
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