Invertebrates in Your Reef: Shrimp, Starfish & Snails
A guide to adding invertebrates that help your reef thrive
---
Why Invertebrates Matter
Invertebrates aren't just decorative. They: - Clean your tank (snails eat algae, shrimp remove detritus) - Reduce disease (cleaner shrimp eat parasites off fish) - Improve water quality (starfish stir substrate, natural waste processors) - Add activity (they're interesting to watch)
Best part: Most are compatible with corals and fish.
---
The Major Invertebrate Groups
Cleaner Shrimp
Examples: Coral Banded, Fire Red, Skunk Cleaner, Peppermint
What they do: - Remove parasites from fish - Eat dead skin and debris - Establish "cleaning stations" (fish come to get cleaned) - Beautiful and active
Tank needs: - 20+ gallons (most species) - Plenty of hiding places (rockwork, caves) - Feed: occasional supplements (they eat naturally)
Price: $25-60 per shrimp
Compatibility: - ✅ Fish: Get along with most - ✅ Corals: Won't bother them - ⚠️ With each other: Depends on species (some can fight)
Pro tip: Keep only 1 cleaner shrimp per small tank (20-30g). Can keep 2-3 in larger tanks (60g+) if species-compatible.
---
Starfish (Sea Stars)
Examples: Red (Fromia), Blue (Linckia), Chocolate Chip, Seastar
What they do: - Stir substrate (aerate) - Eat algae and detritus - Beautiful coloration - Long-lived (can live 5+ years)
Tank needs: - 40+ gallons (most species) - Soft substrate (they're sensitive to sharp rock) - Stable water quality (picky about chemistry) - Low bioload (they don't like high waste)
Price: $40-100+ per star (some are expensive)
Compatibility: - ✅ Corals: Usually fine - ✅ Fish: Won't bother them - ❌ With each other: Most are territorial (keep only 1 species per tank)
WARNING: Some starfish (Chocolate Chip) are carnivorous and eat corals/inverts. Do your research before buying.
---
Snails
Examples: Cerith (small), Turbo (large), Trocchus, Astrea
What they do: - Eat algae constantly - Clean rockwork - Very low bioload - Cheap and abundant
Tank needs: - Any size (even tiny snails work in 20g) - Feed: Just algae in tank (rarely need supplementation) - Stable tank (they die if water quality drops)
Price: $5-15 per snail (cheapest invert option)
Compatibility: - ✅ Everything (snails are peaceful) - ✅ Corals: Won't sting or bother - ✅ Fish: Fish won't bother snails (usually)
Best stocking: 1 snail per 5-10 gallons. (Small 20g = 2-4 snails)
---
Urchins
Examples: Red Sea, Purple, Slate Pencil
What they do: - Aggressive algae eaters - Stir substrate - Long-lived - Very hardy
Tank needs: - 40+ gallons (they get large and move around) - Low flow (they're slow) - Stable water quality - Hiding places
Price: $40-70 per urchin
Compatibility: - ✅ Corals: Usually OK (but they accidentally knock things over) - ✅ Fish: Won't bother them - ❌ With each other: Territorial (1 per tank)
WARNING: Slate pencil urchins will break/damage delicate corals. Be careful placement.
---
Clams (Advanced)
Examples: Tridacna, Maxima, Derasa
What they do: - Filter feed (eat plankton) - Colorful shells - Beautiful to watch - Long-lived (10+ years)
Tank needs: - 50+ gallons minimum - High light (they have symbiotic algae) - High flow (brings food) - Stable water quality - Advanced keeper (not beginner)
Price: $100-500+ (expensive)
Compatibility: - ✅ Corals: Won't bother - ✅ Fish: Won't bother - ❌ Aggressive inverts: Some will eat clams
Verdict for beginners: Skip for now. Start with shrimp, snails, stars.
---
Compatibility Matrix: Which Can Live Together?
| Cleaner Shrimp |
| Snails |
| Cleaner Shrimp |
| ✅ Yes |
| ✅ Usually |
| Starfish |
| ❌ Territorial |
| ❌ Will fight |
| Snails |
| ⚠️ Star might eat |
| ✅ Usually |
| Urchin |
| ❌ Will fight |
| ❌ Only 1 per tank |
Key takeaway: Snails and shrimp are your safest bets. Starfish and urchins need their own space.
---
Best Invertebrate Combinations by Tank Size
20-30 Gallon Tank
Safe combination: - 1-2 Cleaner shrimp - 3-4 Snails (cerith, turbo)
Do NOT add: Starfish or urchins (too large for tank bioload)
---
40-60 Gallon Tank
Option 1 (Cleaning focus): - 2 Cleaner shrimp - 5-6 Snails - 1 Starfish (Red or Blue)
Option 2 (Algae control focus): - 1-2 Urchins - 8-10 Snails - 1 Cleaner shrimp
Mix and match as needed.
---
75+ Gallon Tank
Full invertebrate reef: - 3-4 Cleaner shrimp (different species) - 2 Starfish (different species) - 1 Urchin - 10-15 Snails - 1-2 Clams (if advanced)
---
Adding Invertebrates: Timeline & Acclimation
Before Adding
1. Research compatibility with your specific corals and fish 2. Ensure stable water chemistry (most important for inverts) 3. Have hiding places ready (especially for shrimp)
Acclimation Process
Simple acclimation (same as fish):
1. Float the shipping bag in tank (15-20 min) 2. Slowly introduce tank water to bag (drip method, 20 min) 3. Gently net and place in tank 4. Turn lights off for 1 hour 5. Resume normal routine
Why important: Invertebrates are sensitive to salinity and pH changes.
---
Feeding Invertebrates
Cleaner Shrimp
- Feed: Naturally (eat parasites/detritus) - Supplemental: Occasional tiny pellets or frozen food - Frequency: 2-3x per week (small amounts)Starfish
- Feed: Naturally (eat algae/detritus) - Supplemental: Rarely needed - If needed: Specialized starfish food (rare)Snails
- Feed: Naturally from algae in tank - Supplemental: Not needed if algae is present - If starving: Blanched zucchini or spinach (once per week)Urchins
- Feed: Naturally from algae - Supplemental: Occasional kelp or algae wafers---
Common Invertebrate Problems
Shrimp Disappeared or Died
Causes: - Too aggressive fish ate it - Molting (may look dead, but hiding) - Poor water quality - Lack of hiding places
Prevention: - Provide dense rockwork for hiding - Don't keep with aggressive fish (large tangs, etc.) - Maintain stable water quality
---
Starfish Won't Move / Appears Stuck
Causes: - Acclimating (normal, may take 24 hours) - Eating biofilm (looks motionless) - Stuck on something (not actually stuck) - Dying from poor water quality
Fix: - Wait 24+ hours - Don't disturb it - Check water parameters
---
Snails Climbing Out / Dying
Causes: - Poor water quality (snails are canaries for this) - Predatory fish eating them - Lack of algae (starvation)
Prevention: - Monitor water quality religiously - Don't keep with aggressive fish - Ensure tank has enough algae
---
Inverts Molting (Scary!)
What's happening: They're shedding their exoskeleton to grow. Looks like the animal died.
What to do: - DON'T remove it (the soft animal is inside) - Leave it alone for 24-48 hours - It will emerge and harden
Timeline: - Hours 0-24: Looks "melted" or dead - Hours 24-48: Splits open, animal emerges - Hours 48-72: New shell hardens, becomes active
Normal and healthy. Don't panic.
---
Health Signs vs. Problem Signs
✅ Healthy Signs:
- Moving around constantly (shrimp, stars) - Eating/grazing (snails on glass/rock) - Normal coloration - Responsive to feeding⚠️ Problem Signs:
- Not moving for 24+ hours (except during molt) - Discoloration (fading, brown spots) - Broken spines/appendages - Unresponsive to food---
Timeline: First 30 Days with Inverts
| Day |
| 0 |
| 1 |
| 2-3 |
| 4-7 |
| 7-14 |
| 14-30 |
---
EasternMarine Invertebrate Starters
Cleaner Shrimp Bundle ($79)
Includes: - 2 Coral Banded shrimp - 5 Cerith snails - Care guide---
Starfish & Snail Pack ($99)
Includes: - 1 Red Starfish - 10 mixed snails - Placement guide---
Full Cleanup Crew ($129)
Includes: - 2 Cleaner shrimp - 1 Red Starfish - 10 Snails - Complete care guide---
Next Steps
1. Choose your invertebrates based on tank size 2. Verify compatibility with your existing animals 3. Prepare hiding spots (rockwork, caves) 4. Acclimate properly using drip method 5. Monitor for 2 weeks (they're hardy once settled)
---
FAQ: Invertebrate Questions
Q: Will my shrimp eat my small corals? A: No. Cleaner shrimp don't eat corals. They eat parasites and detritus.
---
Q: Can I keep multiple starfish? A: Not same species. Different species can be territorial. Generally: one starfish per tank.
---
Q: My snails are dying. Why? A: Usually water quality (ammonia/nitrite). Test immediately.
---
Q: How often should I feed shrimp? A: They eat naturally. Supplemental feeding only 2-3x per week.
---
Support
Questions about invertebrates?
📧 Email: mdyer.nz@gmail.com 📞 Phone: 09 281 1380
---
Invertebrates turn your reef from beautiful to functional. Start with cleanup crews. 🦐🐚⭐