Gobies are among the most practical and personality-rich fish you can add to a reef aquarium. They fill specific roles that few other fish can match, from turning over sandbeds to standing guard at burrow entrances with pistol shrimp partners. At Top Shelf Aquatics, we house dozens of goby species across our coral farm and holding systems, and we see firsthand which species thrive and which ones struggle when their needs are overlooked.
This goby care guide covers what actually matters for long-term success: reef safety, realistic tank size by type, sandbed requirements, feeding strategies, pistol shrimp pairings, and compatibility with other fish in mixed reef systems. The goal is practical guidance you can apply, not generic care card information.
One important note before diving in: different goby groups behave very differently in captivity. A sand sifting goby has almost nothing in common with a tiny nano goby when it comes to care requirements. Treating all gobies the same is a fast path to losing them.
Goby vs Blenny: How They Really Differ in a Reef Tank
Many reef keepers lump gobies and blennies together because both are small, perching marine fish with big personalities. However, their behavior, diet, and territory use are quite different, and understanding these differences helps you stock your tank intelligently.
Tank zones and daily behavior
Gobies are primarily bottom dwellers. You will find them hovering just above the sand, perched on lower rock ledges, or stationed at burrow entrances. Many species rarely venture into the water column except during feeding frenzies or when startled.
Blennies occupy different real estate. They claim rockwork perches, wedge themselves into crevices, and often establish a “home base” hole they return to repeatedly throughout the day. Species like the lawnmower blenny patrol rock surfaces constantly, while others like the tailspot blenny hold a single favored spot for hours.
This zone difference matters for stocking. A goby and a blenny in the same tank often coexist peacefully because they are not competing for the same space.
Feeding styles and diet differences
Gobies are opportunistic bottom feeders. Sand sifters like the diamond watchman goby constantly process substrate for microfauna and detritus. Shrimp gobies wait at burrow entrances and grab food that drifts within reach. Perching gobies pick small crustaceans and copepods from rock surfaces.
Blennies have a more varied diet profile, and this is where misconceptions cause problems. Many assume all blennies spend their day eating algae off rocks. In reality, only about 40-50% of commonly kept blenny species are dedicated grazers. The bicolor blenny, for example, often shifts to picking at coral polyps when microfauna and algae run low. Meaty-food-oriented blennies can become pushy feeders and may nip at fleshy corals or clam mantles when underfed.
Temperament and territory
Gobies defend a small patch, typically a burrow entrance or a few square inches of sand. They mostly ignore midwater fish entirely. Territorial disputes happen when another bottom-dwelling fish tries to claim the same piece of real estate.
Blennies can become surprisingly territorial around their chosen hole or rock, especially in tanks under 40 gallons. A lawnmower blenny that has claimed a section of rockwork will chase other blennies and sometimes harass similarly sized fish that enter its grazing zone.
Reef impact differences
Gobies are more likely to disturb your sandbed and frags than to nip coral tissue. Active sand sifters create localized sandstorms that can irritate low-lying LPS or zoanthids. Shrimp gobies and their pistol shrimp partners will bury small frags and pile sand against coral bases.
Blennies pose the opposite risk. When underfed or housed in very sterile systems with little film algae, some species will taste-test SPS tips, LPS flesh, or clam mantles. This coral picking behavior increases when nutrition is incomplete or when tanks are heavily skimmed and nutrient-starved.
Sandbed Requirements for Gobies
Why substrate is a make-or-break factor
Substrate choice is one of the most overlooked factors in goby success. For sand sifters and shrimp gobies, the sand bed is not decoration. It is their entire world, providing food access, burrow stability, and gill safety.
The wrong substrate causes problems that take months to become visible. By the time a sand sifter shows obvious weight loss, the damage is already done.
Grain size and material
Sugar-sized to small “special grade” aragonite works best for most burrowing and sifting species. Target a grain size between 0.5-1.5mm.
Crushed coral causes two problems. First, sharp edges can damage gill tissue in fish that constantly process substrate through their mouths. Second, coarse material does not hold burrow shape well, leading to frequent collapses that stress pistol shrimp and their goby partners.
Sand depth guidelines by goby type
Most shrimp gobies and many Valenciennea species do well with 2-3 inches of sand. This provides enough depth for stable burrows without creating excessive anaerobic zones.
For active burrowers, especially those paired with pistol shrimp, consider a deeper zone of 3-4 inches in part of the tank. Pistol shrimp can excavate tunnels 4-8 inches deep, and shallow beds force them to build horizontally, often undermining nearby rockwork.
Rock placement and structural safety
This is critical: rocks should sit directly on the glass or on support structures, not on loose sand. When burrowing gobies and pistol shrimp excavate tunnels beneath unsupported rocks, the entire aquascape can collapse.
In our systems at Top Shelf Aquatics, we place rockwork supports before adding sand. This allows the fish to dig freely without risking a rockslide that could injure livestock or crack glass.
Why shallow or sterile sandbeds cause long-term starvation
Sand sifters in tanks with shallow or sterile substrate slowly starve over 6-18 months. The timeline is long enough that hobbyists rarely connect the cause to the outcome.
Here is what happens: the goby arrives plump from the ocean, where it had access to unlimited substrate and microfauna. In a home aquarium with a 1-inch sand bed and no refugium, the goby exhausts the available food within weeks. It continues to sift, but finds less and less. Weight loss is gradual. By month six, the fish looks thin. By month twelve, it either dies or is so emaciated that recovery is unlikely.
Feeding Gobies: Diet, Schedule, and Avoiding Starvation
The core mistake
“They eat what they find in the sand” is not a feeding plan. It is a recipe for slow starvation in most home aquariums.
Wild gobies have access to vast substrate areas with constantly replenishing microfauna. Your tank does not replicate this unless you have a large, mature system with an active refugium.
What to feed most gobies
The foundation of goby feeding is frozen foods that sink and scatter across the bottom:
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Mysis shrimp (high protein, readily accepted)
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Enriched brine shrimp or frozen brine shrimp (good variety, lower nutrition)
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Small planktonic blends
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Finely chopped seafood (shrimp, clam, fish)
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Sinking pellets (once the goby learns to accept them)
Shrimp gobies and perching gobies often accept pellet foods after acclimation. Sand sifters are harder to transition because they are wired to process substrate, not grab floating or sinking particles.
Feeding frequency and delivery
Gobies do best with frequent small feedings rather than one large daily meal. Two to three feedings daily allows food to reach the bottom before faster fish intercept everything.
In community reef tanks, the biggest challenge is competition. Tangs, wrasses, and clownfish will take food before it ever reaches a goby waiting near the sand. You need strategies to work around this.
Practical feeding techniques
Target feeding near burrows: Use a pipette or turkey baster to deliver frozen foods directly to the area where your goby stations itself. This bypasses midwater competition entirely.
Feed near substrate, not just water column: Scatter some food along the bottom rather than broadcast feeding at the surface. This gives bottom feeders a chance.
Adjust flow during feeding: Temporarily reducing powerhead output for 5-10 minutes allows food to settle rather than getting swept into overflow boxes or filtration.
Feed at lights-out: Shy gobies often emerge more confidently in dim lighting. Feeding just before or after lights go out can increase food intake for nervous specimens.
How to spot underfeeding early
Watch for these signs before they become severe:
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Sunken belly (sides pinched inward behind the head)
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Hollow cheeks
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Reduced activity and less time spent at burrow entrances
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Decreased territorial behavior
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Hiding more than usual
If you see early signs of underfeeding, increase feeding frequency and volume before assuming disease. Many “sick” gobies are simply starving.
Shrimp Gobies and Pistol Shrimp Pairings
How the symbiosis works in a home tank
The shrimp goby and pistol shrimp partnership is one of the most fun to watch behaviors you can witness in a home aquarium. The nearly blind pistol shrimp builds and maintains an elaborate burrow system. The goby acts as a lookout, perching at the entrance and signaling danger with body movements and tail flicks.
In the wild and in well-set-up tanks, the shrimp constantly touches the goby with its antennae to maintain contact. When the goby retreats into the burrow, the shrimp follows. When the goby relaxes, the shrimp ventures out to excavate.
This partnership adds interest to even simple tank setups and gives both animals a better chance at long-
What to expect
Pistol shrimp are relentless excavators. Expect:
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Constant sand rearranging, especially in the first few weeks
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Temporary cloudiness when new burrow branches are dug
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Mounds of sand and rubble accumulating near the burrow entrance
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The goby sitting half-out of the burrow, tracking activity in the tank day long
The burrow system will expand over time. Mature pairs in established tanks often have multiple entrances and exits spread across several inches of sand.
Common issues and fixes
Undermined rockwork: If rocks are sitting on sand, the shrimp will excavate beneath them. Secure all rocks before adding sand.
Buried frags: Coral frags placed on sand near the burrow zone will get buried or knocked over. Elevate frags on small plugs or rock pedestals.
Sand on corals: The shrimp’s excavation throws sand onto nearby corals. Keep low-lying corals away from active burrow zones.
Burrow collapse from high flow: Excessive flow over the sand can erode burrow entrances and cause collapses. Position powerheads to avoid direct flow over the burrow area.
Compatibility basics
Not every pistol shrimp will pair with every goby. Species from the same geographic region and of compatible size have the best success rates. The Yellow Watchman Goby pairs reliably with Randall’s Pistol Shrimp and Tiger Pistol Shrimp.
Mismatched sizes cause problems. A large pistol shrimp can bully a small goby out of the burrow entirely. Aim for a goby that is at least as large as the shrimp, or slightly larger.
Your best option is to purchase a known compatible combo or add both animals to the tank at the same time. Pairs that bond in the store or during shipping almost always maintain that bond in your tank.
Goby Behavior, Territory, and Tankmates
Normal body language
Healthy gobies display predictable behaviors once established:
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Hovering just above the sand or perching on low rock ledges
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Quick dashes into burrows when startled, followed by cautious re-emergence
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“Yawning” displays with mouth open wide, used as warnings to nearby fish
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Tail flicking when partnered with pistol shrimp
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Slow, methodical movement through their territory
Constant hiding or frantic darting typically indicates stress from tankmates, poor water conditions, or insufficient hiding spots.
Territory and bottom-dweller conflict
Most gobies claim a relatively small territory centered on a burrow or favored rock. Conflict arises when another bottom-dwelling fish tries to occupy the same patch of sand or the same cave.
Avoid stocking multiple territorial gobies in tanks under 50 gallons unless you can provide completely separate zones with visual barriers. A single aggressive bottom dweller can prevent a shy goby from ever feeding properly.
Good tankmate profiles
Gobies coexist well with:
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Peaceful clownfish (they rarely interact)
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Small wrasses that focus on rockwork and midwater zones
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Chromis, anthias, and other peaceful fish that school in the water column
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Peaceful dwarf angels
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Most shrimp and snails
The key is choosing fish that occupy different tank zones and do not compete for food at the substrate level.
Common problem tankmates
Some fish cause consistent problems:
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Aggressive wrasses: Six-line wrasses and some fairy wrasses harass bottom dwellers relentlessly
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Large hermit crabs: They compete for burrows and can injure or kill small gobies
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Boisterous feeders: Fish that create chaos at feeding time prevent shy gobies from eating
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Other territorial bottom dwellers: Jawfish, other gobies of similar size, or aggressive blennies
In the near future, always research new additions before they go into your main tank with established gobies.
“Disappearing goby” scenarios
New gobies frequently vanish into rockwork for days or even weeks after introduction. This is normal. They are finding hiding spots, mapping the tank, and waiting until they feel safe.
Before assuming a goby is dead:
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Check all gaps in your lid and around equipment (gobies jump)
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Watch the tank at night with a dim flashlight
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Look for subtle movement in rock crevices
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Continue offering food near suspected hiding spots
Gobies that are alive but hiding will eventually emerge once they feel secure. Gobies that jumped will be found on the floor or dried behind the stand.
Reef Safety: Gobies in Mixed Coral Tanks
What “reef safe” means for gobies
Gobies are generally reef safe in the traditional sense. They rarely nip coral tissue, ignore clams, and do not pick at invertebrates. However, their digging and sifting behaviors can still affect coral health through physical disturbance.
“Reef safe” for gobies means safe for coral tissue, but plan your layout to minimize sandstorm exposure and burial risk.
Sandstorms and coral placement
Active sand sifters create localized sandstorms as they process substrate. Sand particles blown onto coral tissue cause irritation. LPS corals like open brains and acans placed directly on sand in a sand sifter’s work zone will receive constant sand exposure.
Elevate sensitive corals on rock islands above the sand sifting zone. Zoanthids and low-growing LPS do best at least 3-4 inches above the substrate when housed with active sifters like the diamond goby.
Shrimp gobies and pistol shrimp collateral damage
Pistol shrimp move incredible amounts of sand. They pile excavated material near burrow entrances, bury objects in their path, and knock over unstable items.
Small frag plugs placed on sand will be buried within days. Rubble pieces will be incorporated into burrow construction. Anything not secured will move.
Prevention strategies:
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Mount frags on rock or frag racks above the sand
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Keep burrow zones away from your most valuable coral placement areas
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Accept that some sand will accumulate on lower corals near active burrows
Clown gobies and SPS perching
Clown gobies (Gobiodon spp.) naturally perch inside branching corals. In the wild, they live among Acropora branches and receive protection from the coral structure.
In aquariums, this behavior can irritate coral tissue and stunt branch growth where the goby perches repeatedly. SPS-dominant keepers should either accept this trade-off or place clown gobies in tanks with non-branching corals.
Layout strategy
Plan your aquascape with goby behavior in mind:
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Designate burrow zones toward the front or sides where sand disturbance will not affect corals
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Elevate delicate corals on stable rock islands away from frequent digging paths
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Use rock pillars or arches to create vertical separation between sand zones and coral zones
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Leave open sand areas for sifters rather than covering the entire bottom with rock
Gobies and Blennies Together
The goby and blenny combination works well in many tanks. Both are great fish with distinct personalities, and they usually occupy different zones without conflict.
Success factors:
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Tank size of 40 gallons or more
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Multiple rock structures creating visual breaks
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Both fish well-fed on appropriate diets
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Different species rather than multiple of their own kind
Territory overlap becomes an issue in smaller tanks where a blenny’s grazing zone overlaps with a goby’s burrow zone. In tanks under 30 gallons, one fish often dominates and the other hides constantly.
Blenny coral picking happens when:
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Film algae is depleted (heavily skimmed, low-nutrient systems)
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The blenny is not receiving other foods to compensate
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The tank is overstocked and competition is high
A well-fed blenny with access to nori sheets, algae pellets, and natural film growth rarely picks at corals. Problems arise in very lean systems or when hobbyists assume the blenny is “eating algae” and needs no supplemental feeding.
Monitor early interactions after adding a blenny to a tank with an established goby. Rearranging rockwork or rehoming one fish is sometimes necessary if aggression focuses on the burrow area.
Acclimation, Quarantine, and Long-Term Care
Acclimation priorities
Gobies are sensitive to rapid changes in salinity and ph level. Ship-shocked gobies that experience sudden parameter swings often die within days or never recover their feeding response.
Acclimate slowly. Drip acclimation over 45-60 minutes works well for most species. Match temperature closely before release.
Quarantine setup that actually works for gobies
Standard bare-bottom quarantine tanks suppress natural goby behavior. A goby sitting on bare glass with no cover often refuses to eat and shows chronic stress.
Better QT setup for gobies:
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Small covered tank (10-20 gallons)
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PVC fittings or short tunnels for hiding
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Optional: small container with 1 inch of sand for burrowing species
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Dim lighting initially
This allows observation and treatment if needed while encouraging the goby to behave normally and accept food.
Training gobies to eat prepared foods
Quarantine is the ideal time to train gobies onto prepared foods before they enter your display. Competition is eliminated, and you can control exactly what reaches the fish.
Offer small amounts of frozen foods near the goby’s hiding spot 2-3 times daily. Start with mysis shrimp or other foods that smell strongly and sink slowly. Once the goby is eating frozen foods confidently, introduce pellets.
Shrimp gobies typically transition within 1-2 weeks. Sand sifters may never fully transition but will accept target-fed frozen foods as a supplement.
Long-term expectations
Gobies are multi-year fish when their needs are met. We see watchman goby specimens in customer tanks that have been thriving for 3-5 years. Sand sifters with adequate substrate and supplemental feeding often live 4-6 years.
Long-term success requires:
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Stable reef parameters (consistent salinity, low nitrate levels, stable temperature)
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Consistent feeding appropriate to the species
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Appropriate substrate for the goby type
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Secure lids
Gobies that fail typically do so from starvation, jumping, or harassment from incompatible tankmates. Address these factors and your goby becomes a reliable long-term resident.
Common Problems and Troubleshooting
Goby hides constantly
Normal for the first 1-2 weeks. Beyond that, check for aggressive tankmates, excessive flow near hiding spots, or insufficient cover. Try feeding at lights-out to encourage emergence.
Goby loses weight slowly
Almost always a feeding problem. Increase feeding frequency, target feed near the goby’s location, and ensure food reaches the bottom before competitors take it. Sand sifters in small tanks may need refugium support or a larger system.
Sandstorms and coral irritation
Relocate affected corals above the sand sifting zone. Consider whether the goby’s work area can be shifted by moving rockwork or adding a preferred sifting zone away from corals.
Burrow collapse or rock undermining
Secure all rockwork to the glass before adding sand. This is not fixable after the fact without major tank disruption.
Jumping incidents
Gobies are expert jumpers. Prevention checklist:
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Tight fitting lid with no gaps larger than 1/4 inch
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Mesh covers over overflow boxes
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Screen or foam blocking gaps around plumbing and cords
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Check the floor behind the tank if a goby goes missing
Goby Species Index
Sand sifters
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Diamond Watchman Goby (Valenciennea puellaris)
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Sleeper Blue Dot Goby (Valenciennea sexguttata)
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Tiger Watchman Goby (Valenciennea wardii)
Shrimp gobies
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Yellow Watchman Goby (Cryptocentrus cinctus)
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Randall’s Shrimp Goby (Amblyeleotris randalli)
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Yasha Goby (Stonogobiops yasha)
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Hi Fin Red Banded Goby (Stonogobiops nematodes)
Perching gobies
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Neon Goby (Elacatinus oceanops)
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Clown Gobies (Gobiodon spp.)
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Court Jester Goby (Koumansetta rainfordi)
Nano gobies
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Trimma species
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Eviota species
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Pretty prawn gobies
FAQ
Do gobies need sand?
It depends on the species. Sand sifters and shrimp gobies require sand and will not thrive without it. Perching gobies and nano gobies can live in tanks with minimal sand or rock-heavy aquascapes.
Are gobies reef safe?
Yes. Gobies rarely nip corals or clams. Their reef impact comes from physical disturbance through digging and sand movement, not from eating coral tissue.
How often should I feed a goby?
Two to three small feedings daily works best. Gobies are small fish with high metabolisms that do better with frequent meals than one large feeding.
Why did my goby disappear?
Either it is hiding in rockwork (common for new additions) or it jumped out of the tank. Check for lid gaps and look behind the stand. If the goby is hiding, continue feeding normally and watch at night.
Will a goby pair with any pistol shrimp?
No. Compatibility depends on species, size, and geographic origin. The best results come from purchasing known compatible pairs or adding both animals simultaneously.
Can I keep more than one goby?
Yes, in larger tanks (75+ gallons) with separated territories. Avoid stocking similar-shaped gobies that want the same burrow or sand patch. Different goby types occupying different niches coexist best.
Planning ahead for your goby’s specific needs is the difference between a fish that thrives for years and one that slowly fades. With the right substrate, appropriate tank size, and consistent feeding, gobies become reliable long-term residents and a great addition to modern reef tanks.