Can Molly Live With Rummy Nose Tetra?
Maybe, mollies and rummy nose tetras might coexist in 20 gallons or larger, though both species have specific needs that could clash in some setups.
Why
- Temperature overlap sits at 75-82F, which suits both species, and pH overlap at 7.0 is workable for both.
- Mollies grow to 4-5 inches and are active swimmers that may intimidate smaller rummy nose tetras in smaller tanks.
- Rummy nose tetras are schooling fish that need groups of 6 or more to feel secure and display their best colors.
- Mollies prefer slightly brackish water over time, while rummy nose tetras are strict freshwater fish that do not tolerate salt.
- Mollies are livebearers that produce lots of waste, which can degrade water quality and stress sensitive rummy nose tetras.
What could go wrong
Rummy nose tetras are sensitive to water quality changes, and a bioload spike from active mollies may cause them to lose their distinctive red coloring or fall ill.
Gear for a shared tank
Sized for the 20 gallon minimum this pairing needs. Affiliate links — we earn a small commission if you buy through them.
AquaClear 30 Power Filter
Oversized filtration is what lets you stock two species together without water quality crashing. Rated for a tank slightly larger than the 20 gallon minimum.
Eheim Jager 150W Thermostat Heater
Holds a steady temperature inside the 75-82°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
For a molly community tank, consider keeping them with other livebearers like platies or guppies, or keep rummy nose tetras with other peaceful schooling fish.
Related compatibility questions
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