East Indies siltgoby

Where they come from

The East Indies siltgoby (Amblygobius cheraphilus) shows up around Indonesia and nearby areas where the bottom is basically sand, silt, and rubble. They spend their whole day close to the substrate, grabbing mouthfuls of sand and spitting it out while they hunt tiny edible bits.

That natural lifestyle explains almost everything about keeping them: give them real sand to work, calm-ish tankmates, and food that actually reaches the bottom.

Setting up their tank

If you want this fish to look relaxed and act natural, start with the substrate. They are sand-sifters. Bare bottom tanks and sharp gravel just do not match how they feed and can lead to a beat-up mouth over time.

• Tank size: I would not do one in less than 30 gallons, and 40+ is nicer if you have other fish.
• Substrate: fine sand, enough depth that they can scoop and sift (think 2-3 inches).
• Rockwork: stable rock structures sitting on the glass or on a solid base, not on loose sand they can dig under.
• Flow: moderate. You want oxygen and clean water, but not a sandstorm all day.
• Cover: a lid helps. Gobies can and do jump when spooked.

They appreciate some little caves and shaded spots, but they are not a classic "hide all day" goby. Mine spent plenty of time out front sifting as long as the tank was not full of pushy fish.

What to feed them

In the store they often look like they should be easy because they are always "eating" sand. The catch is that sifting is how they find food, but your tank sand may not have enough nutrition in it, especially in newer setups.

• Staples: frozen mysis, brine (better as a treat), finely chopped shrimp, and good frozen blends.
• Small foods: copepods, enriched live baby brine, and pellets that sink quickly (small size).
• How to feed: target the bottom. I like using a turkey baster to puff food into the sand area they work.
• Schedule: smaller portions 1-2 times a day beats one big dump, especially early on.

If you keep one in a new tank with "clean" sterile sand, plan on feeding more heavily at first. Once your system matures and the sandbed has some life, they often look better and spend less time frantically searching.

How they behave and who they get along with

These are generally peaceful bottom fish. They are busy, curious, and not very interested in starting fights, but they can get stressed if bigger fish constantly rush them at feeding time.

• Good tankmates: calmer wrasses, cardinals, chromis, smaller tangs (in bigger tanks), blennies that are not overly territorial.
• Use caution with: dottybacks, aggressive damsels, large hawkfish, and anything that claims the whole bottom as "its" turf.
• Other gobies: depends on space and personality. Two sand-sifters in a small tank usually turns into bickering.
• Inverts: usually reef-safe. They may eat tiny worms and pods (that is kind of the point), but they typically ignore cleaner shrimp and snails.

One more thing: they are notorious for redecorating. If you have a delicate sandbed aquascape with tiny rocks balanced on sand, this is not the fish for that layout.

Breeding tips

Breeding Amblygobius gobies in home tanks is possible, but it is not a "oops babies" situation for most people. They are typically cave or burrow spawners, and the hard part is raising the larvae, not getting eggs.

• If you want to try: give them multiple caves/tunnels and keep them well fed.
• Pairs: a bonded pair will often claim a spot and become more defensive around it.
• Larvae: expect tiny planktonic fry that need live foods (rotifers, then nauplii/pods) and stable rearing conditions.

Common problems to watch for

Most issues with this species come from three things: not enough food making it to the goby, the wrong substrate, or stress from tankmates.

• Starvation while "sifting": they look busy but lose weight. Fix by target feeding and offering richer foods.
• Mouth damage: sharp gravel or crushed coral can scrape them up. Fine sand is safer.
• Jumping: especially after adding new fish or during tank maintenance. Use a lid and keep the room lights from startling them.
• Sandstorms: too much flow aimed at the bottom, or very fine powdery sand. Redirect pumps or mix in slightly coarser sand if needed.
• Parasites and shipping stress: new imports can come in thin. Quarantine helps, and gentle feeding gets them back faster than chasing them around.

If you give them a real sandbed, steady meals, and a tank where they are not getting bullied off the bottom, they are one of those fish you end up watching more than you expected. The constant sift-spit-sift routine is oddly relaxing.