Scuds (Gammarus) are one of the most versatile live foods you can culture at home. Whether you're feeding pea puffers, enriching your aquarium with a natural cleanup crew, or building a self-sustaining live food colony, this complete care guide will show you exactly how to culture, feed, and maintain healthy scud populations.
What Are Scuds? (Gammarus spp.)
Scuds (Gammarus spp.) are small freshwater amphipods — hardy crustaceans commonly used as live fish food, cleanup crew, and micro‑ecosystem builders. They thrive in simple setups, reproduce steadily, and help maintain water quality by eating detritus, algae, and leftover food.
Aquarists keep scuds for:
- feeding pea puffers, bettas, cichlids, and other nano predators
- enriching tanks with natural foraging behavior
- maintaining biofilm‑rich, self‑sustaining ecosystems
- starting long‑term live food cultures at home
How to Set Up a Scud Culture (Beginner‑Friendly Guide)
- Add scuds to a container or tank with dechlorinated water.
- Add a small piece of food (algae wafer, blanched veggie, or leaf litter).
- Provide hiding places like moss, sponge, or botanicals.
- Keep at room temperature; gentle aeration is optional but helpful.
What Scuds Eat — Best Foods for Gammarus
Scuds are omnivorous detritivores, meaning they eat both plant‑based and protein‑based foods, with a strong preference for biofilm and decaying matter.
Best Foods
- Algae wafers
- Blanched vegetables (zucchini, spinach, green beans)
- Fish flakes or pellets
- Biofilm and mulm
- Indian almond leaves or botanicals
- Light feedings of Chlorella or Tetraselmis
Feeding Tips
- Feed lightly — scuds don’t need much.
- Uneaten food should be minimal after 24 hours.
- Biofilm is their favorite long‑term food source.
- A little mulm actually helps the colony grow.
How to Feed Scuds to Fish (Live Food Guide)
Scuds are one of the best live foods for freshwater fish, offering high nutrition and natural hunting enrichment.
Fish That Eat Scuds
- Pea puffers
- Bettas
- Dwarf and medium cichlids
- Rainbowfish
- Barbs
- Loaches
- Axolotls & newts
- Larger tetras
- Any nano predator
How to Feed
- Scoop scuds with a net, cup, or turkey baster.
- Rinse briefly in clean water.
- Add directly to the tank — they’ll swim, hide, and trigger natural foraging.
- For picky fish, release a few at a time to spark interest.
Feeding Notes
- Scuds are nutrient‑dense; small portions go far.
- Excellent for conditioning breeders.
- Great enrichment for puffers and bettas.
- To seed a tank with scuds, add them after lights out.
Ready to start your own scud colony? Get live scuds HERE!
Water Parameters for Scuds (Temperature, Aeration, Water Changes)
Container Size
- Jars, buckets, totes, or tanks all work
- Larger volumes = more stable populations
Temperature
- Room temperature (65–78°F)
- Avoid sudden swings
Aeration
- Gentle bubbling is helpful
- Too strong can stress or injure them
Water Changes
- Replace 10–30% weekly
- Use dechlorinated water
- Match temperature to avoid shock
How to Breed and Expand Your Scud Colony
- Prepare a clean container with dechlorinated water.
- Add hiding structures (leaf litter, moss, sponge, mesh).
- Transfer a portion of your scuds.
- Add a small amount of food.
- Keep water clean and stable.
Scuds reproduce steadily — expect visible population growth within a few weeks.
How to Harvest Scuds Safely
- Use a net, cup, or turkey baster.
- Rinse briefly before feeding fish.
- If maintaining a colony, leave plenty of juveniles behind.
- If feeding immediately, you may harvest freely.
Scud Troubleshooting — Common Problems & How to Fix Them
Population Not Growing
- Not enough hiding places
- Not enough food
- Water too clean (they love mulm)
- Temperature too low
Water Smells Bad
- Overfeeding
- Not enough water changes
- Remove excess food and refresh water
Scuds Dying Off
- Chlorine/chloramine exposure
- Sudden temperature change
- Strong aeration
- Copper contamination
Scuds FAQ — Answers to Common Questions
Can scuds live in a fish tank?
Yes — but most fish will eat them. They survive best in low‑predation or shrimp‑friendly tanks.
Do scuds eat algae or plants?
Scuds eat algae, biofilm, and detritus. They rarely damage healthy plants but may nibble on soft or dying leaves.
Do scuds need aeration?
Aeration is helpful but not required. Gentle bubbling improves oxygen and reproduction.
What temperature do scuds need?
Room temperature (65–78°F) is ideal.
How fast do scuds reproduce?
Under good conditions, scuds reproduce steadily and populations can double in a few weeks.
Why are my scuds dying?
Common causes include chlorine, overfeeding, strong aeration, copper, or sudden temperature changes.
Can scuds live with shrimp?
Yes — but adult scuds may prey on baby shrimp
Can scuds live with snails?
Yes — they are fully compatible with all freshwater snails.
Do scuds need substrate?
No, but leaf litter, moss, or sponge provides hiding places and boosts reproduction.
Can scuds establish a colony in my aquarium?
Yes — if the tank has hiding places and low predation. Add them after lights out for the best chance.
What should I feed my scuds?
Algae wafers, blanched veggies, fish food, botanicals, and light phytoplankton feedings.
Do scuds clean the tank?
Yes — they help break down detritus, leftover food, and biofilm.
Are scuds safe for bettas and puffers?
Yes — they are excellent enrichment and live food for both.
Can scuds survive in cold water?
They tolerate cooler temperatures but reproduce more slowly.
How do I start a scud culture from a small starter portion?
Provide hiding places, feed lightly, and avoid overcleaning. They multiply steadily over time.