Fulvopelvis shrimpgoby

Where they come from

Fulvopelvis shrimpgobies (Vanderhorstia fulvopelvis) are Indo-Pacific sand flat and rubble gobies. Think shallow areas with gentle flow, lots of fine sand, and little bits of shell and coral rubble. They are built for a life spent hovering an inch off the bottom and diving into a burrow the second something looks at them funny.

Most of the ones you see in the trade are wild-caught, and they act like it at first: shy, jumpy, and very burrow-focused. Once settled, they become one of those fish you find yourself watching for way too long.

Setting up their tank

This is an advanced fish mostly because you are not really keeping just a goby. You are keeping a burrow, a sandbed, and usually a shrimp partnership all at once. If the bottom of the tank is an afterthought, this goby will make that obvious fast.

• Tank size: I would not bother under 20-30 gallons, and bigger is easier because they feel less exposed.
• Sandbed: fine sand, not crushed coral. Around 2-3 inches works well so the shrimp (if you do a pair) can build without hitting glass immediately.
• Rubble: scatter small chunks of coral rubble and empty shells near the area you want them to claim. They use it like bricks at the burrow entrance.
• Rockwork: stable and sitting on the tank bottom, not on the sand. Burrowers undermine sand and can topple rocks.
• Flow: moderate is fine, but avoid blasting the sandbed. A constant sandstorm stresses them out and fills their burrow.

If you want the classic setup, add a compatible pistol shrimp. Not every pistol shrimp is a good match, but Alpheus randalli and Alpheus bellulus are common choices that often work with Vanderhorstia-type gobies. Even then, partnerships are not guaranteed. Give them time and give them a burrow zone away from heavy traffic.

What to feed them

These gobies are micro-predators. In the wild they pick at tiny crustaceans and worms drifting by. In a tank, the goal is getting them confidently eating prepared foods without letting faster fish steal everything.

• Best staples: mysis (smaller pieces), chopped brine, finely chopped seafood, and good quality marine pellets once they accept them.
• Frozen that works well: calanus, cyclops, roe, and enriched brine shrimp (brine alone is more like potato chips).
• Live help for new/shy arrivals: live copepods, live enriched brine, or small live mysis if you can get it.

Target feeding makes a huge difference. I use a turkey baster or a feeding tube and gently puff food right up-current of the burrow entrance. They will hover, grab, retreat, repeat. If you broadcast feed in a tank with tangs or anthias, the goby often gets the scraps.

How they behave and who they get along with

Once settled, they are classic watchman behavior: hovering at the burrow entrance, quick dashes to grab food, and instant retreat when spooked. If paired with a pistol shrimp, you will see the goby acting as the lookout while the shrimp bulldozes sand. The goby will often keep a fin or body contact with the shrimp, which is half the fun of keeping them.

• Temperament: peaceful, but they want their little patch of sand respected.
• Good tankmates: calm reef fish like clownfish, smaller wrasses that are not bullies, cardinals, and peaceful blennies.
• Use caution with: very active feeders (anthias, big wrasses), dottybacks, hawkfish, and anything that likes to perch near the burrow and stare.
• Avoid: sand-sifting gobies that compete for the same niche, and aggressive bottom fish that will claim the same real estate.

Corals are usually fine, but the shrimp can bury low frags. If you are into neat, tidy sand, this pair is not your dream. They will redecorate. I have had them pile sand against frag racks and build little "walls" overnight.

Breeding tips

Breeding in a typical home reef is more of a "cool if it happens" thing. A bonded pair may spawn in the burrow, and you might notice the male looking extra guard-y or the pair disappearing for longer stretches. The eggs are usually laid inside the burrow, and the larvae are planktonic, which is where it gets tough.

• If you want a real shot: species tank or very calm community, stable temperature and salinity, and a well-established pod population.
• Larval rearing: plan on a separate larval setup, rotifers, and later copepods. Most people fail here the first few times, so do not feel bad.
• Best "breeding tip" for most hobbyists: focus on getting them fat, calm, and secure. Spawning behavior tends to follow.

Common problems to watch for

Most issues with Fulvopelvis shrimpgobies come down to stress, not eating enough, or getting bullied. They do not handle constant chaos on the sandbed.

• Not eating: often a new-fish problem. Try live foods for a few days, then mix in frozen. Feed near the burrow, not across the tank.
• Getting skinny over time: classic sign of food competition. Increase feeding frequency or target feed.
• Jumping: almost always from being spooked (sudden lights, chasing, netting, hands in the tank). Lid fixes most tragedies.
• Burrow collapse or nonstop digging: usually sand too coarse, too shallow, or flow blasting the area. Add fine sand and a bit of rubble.
• Disease after purchase: watch for marine ich and velvet signs (scratching, heavy breathing, dusting). They can crash fast, so quarantine is worth the effort with this fish.

One more practical thing: keep an eye on alkalinity and pH swings if your tank runs on the edge. Bottom dwellers that live at the burrow entrance seem to react to instability faster than some midwater fish. A steady, mature tank beats chasing numbers every time with these guys.