Diamond Goby (Valenciennea Puellaris): Ultimate Care Guide

Diamond Goby is a popular choice for hobbyists due to its ability to sift and clean sand. Also known as Diamond Watchman Goby, Spotted Sleeper Goby and Maiden Goby, this species is a great addition to an aquarium as long as enough food sources are available.

The Diamond Goby spends most of its time near sandy bottoms where it sifts through sand looking for copepods and other microfauna food sources. This feeding method means you will only want to add a Diamond Goby to your collection when a tank has become established. New aquariums won’t have the diversity of microfauna this fish needs. There are ways to feed this species directly with a target feeder but allowing for live food in an established tank is the most natural way to keep your Gobies happy and healthy. In an active tank this feeding behavior helps keep sand clean and turned. Diamond Gobies are prized by hobbyists who want to keep their sand looking good.

Native to Indo-Pacific waters and the Great Barrier Reef, Diamond Goby can reach lengths of 7 inches in the wild. In an aquarium they can reach a maximum of 6 inches. Peaceful with other fishes, Diamond Goby is territorial and can fight with members of its own species. It is best to only keep a single specimen or a mated pair in a tank.

Diamond Goby Care

Diamond Goby are easy to keep as long as a good food source is available. In addition to deep live sand, a refugium with a healthy community of copepods will help ensure live food availability. While live sand is this Goby’s best food source, their sifting behavior can disrupt deep sand beds (DSB) used for nitrate reduction. Hobbyists who use a DSB in their setup should avoid Diamond Goby.

Diamond Goby are hardy once their feeding needs are taken care of. They are usually the most disease resistant fish in an aquarium. This isn’t to say they can’t be carriers. Keep an eye on new Diamond Gobies in a quarantine tank (QT) for a couple of weeks before adding to a community tank.


Diamond Goby prefers temperature in a range from 72° to 79° F.

Water pH

The best alkalinity for Diamond Goby is 8.1 – 8.4 pH.

Diamond Goby (Valenciennea Puellaris)
Diamond Goby (Valenciennea Puellaris)

Diamond Goby Size

In nature Diamond Goby can reach up to 7 inches. In an aquarium they usually reach a maximum size of 6 inches. To get the best growth from your Goby, ensure a steady supply of live copepods and microfauna as well as enough live sand for them to sift.

Food & Diet

Diamond Goby prefer live foods including copepods and other microfauna. They can be fed with prepared food and a target feeder but this is not ideal. Let’s look at some other details about Diamond Goby food sources and feeding techniques.

What do Diamond Goby eat in the wild?

In the wild, Diamond Goby eat copepods and a wide range of microfauna. This carnivorous fish will sift through sand looking for various tiny invertebrates to feed on. In aquariums it is best to try to match this food source with live sand and a refugium.

What to feed Diamond Goby?

The best food source for Diamond Goby in an aquarium comes from having lots of live sand and a refugium to grow a community of copepods. This Goby prefers live foods that it finds itself through sifting sand.

Sometimes it might be necessary to feed your Diamond Goby prepared food. To do this you will need a target feeder and selection of food they might like such as brine shrimp, mysis, live blackworms or similar. Use your target feeder to place food under the sand near your Goby. It should be able to smell this and will, hopefully, eat it through sifting. Once Diamond Goby is used to prepared foods it may not be necessary to place them in the sand. Your Diamond may start taking them right from the target feeder’s tube.

Hand feeding should not be relied on to keep your Diamond Goby healthy. The best method is to have a refugium to grow copepods and other live foods as an addition to your live sand bed. Readily available live food is one of the keys to keeping your Gobies alive!

Will Diamond Goby eat pellets?

Diamond Goby might be coaxed to eat pellets. Pre-soak your pellets or flake in garlic or Seachem’s Garlic Guard to make them more appetizing. Once they begin taking pellets, garlic additives might be unnecessary. It is important to ensure that your Diamond Goby is eating pellets and not just chewing them up and passing them out. They sift sand all day without eating it and can do the same with pellet fragments. Make sure you aren’t underfeeding your Goby unintentionally!

How to fatten up my Diamond Goby?

Some people ask how to fatten up their Diamond Goby. If you think a Diamond Goby is looking thin and in need of fattening up, it may be having problems eating. This species can be easily lost by being placed in a new aquarium without enough natural food sources. Diamond Goby can sift sand all day but if there aren’t enough copepods or other microfauna to eat it will starve.

In an emergency you can buy copepods and add them to your tank. Buying pods for a Diamond Goby can get expensive. It is much better to have a refugium or a well established tank with enough microfauna food available. Diamond Goby is a carnivore and wants live food. They can be coaxed to eat pellets or flake, sometimes with garlic additives, but that might not give them enough nutrition.

Diamond Goby Lifespan

Diamond Goby will live for about 5 years with excellent care.

Diamond Goby Tank Size

You will need at least a 30 gallon aquarium for a Diamond Goby. This species sifts sand and wants a deep sand bed.

Diamond Goby Tank Setup

Diamond Goby will need at least a 30 gallon tank. Between 2 ½ and 3 inches of sugar-fine sand is recommended. Diamond Goby is a sand sifting species and needs enough depth to burrow. This burrowing and sifting behavior can cause problems in two situations. First, is when using deep sand beds (DSB) for nitrate removal. DSBs work with thick layers of sand, up to 6 inches or more. Diamond Goby’s burrowing and sifting can disturb the layered biology of a DSB. Most hobbyists using a DSB will want to avoid including a Diamond Goby. A second issue is moving rocks. If live rocks or other hardscape are set on top of sand, Diamond Gobies can tunnel under it. Sometimes this creates a cave-in and Gobies can be crushed under falling rock. If planning a tank for any Goby, it is best to set rocks and harsdscape on the bottom of the tank before adding sand. This ensures that rocks will be stable even if sand moves around their base.

Sugar-fine sand is recommended, as coarse substrates like crushed coral can be hard on sand-sifting Diamond Gobies. Marine substrates like aragonite sand will dissolve over time. Plan on adding more periodically to allow your Gobies enough material to sift.

Food sources will need particular planning. Diamond Goby is a carnivore and prefers to eat live microfauna such as copepods. A new tank will not have enough microfauna to keep Gobies happy and well-fed. It can be a good idea to include a refugium to serve as a copepod nursery.

Do Diamond Goby needs sand?

If they are eating regularly, Diamond Goby won’t necessarily need sand. Sometimes having them in a tank without sand is beneficial. For instance a quarantine tank (QT) is often bare.

Do Diamond Goby sift sand?

Diamond Goby sift sand for feeding and will bury themselves for protection. Sugar-fine sand is preferred, coarse substrates can be hard on sifting Gobies.

Diamond Goby Hiding

Diamond Goby will hide when in a new tank or when they feel threatened. They can disappear for a while as they burrow through sand. Sometimes they aren’t hiding, just busy looking for food.

Diamond Goby Jumping Out of Tank

Diamond Goby are escape artists and will jump out of a tank without a secure lid. They are very good about finding small openings to get through, so double-check your lid to avoid carpet surfing Gobies.

Diamond Goby Breeding

Diamond Goby are monogamous and a breeding pair is never far apart. Pairing Diamond Gobies can be the hardest part of breeding. After spawning they will place the eggs near their burrow. The male will guard them for a few days until they hatch.

Diamond Goby fry are easy targets for other fish and should be moved to a separate tank to mature. The fry will also need very small food like planktons and SS-type rotifers. If you’re serious about raising Goby fry, consider growing plankton and rotifers for fry food.

It is very difficult to determine Diamond Goby sex. This is made even more difficult as this fish is able to change sexes.

Diamond Goby Disease

Diamond Gobies are resistant to Ich and diseases in general. As long as they are eating and have good water parameters they are often the last fish in a tank to get sick.

Diamond Goby Tank Mates

Diamond Gobies usually prefer hiding over fighting. They are territorial when sharing a tank with other Gobies. Breeding pairs will get along fine.

Are Diamond Goby Aggressive?

Diamond Goby are usually not aggressive. But all fish have their own personalities and aggressive Diamond Gobies are not unknown.

Can I keep 2 Diamond Gobies in the same tank?

You can keep 2 Diamond Gobies in the same tank if they are a breeding pair. Aside from this, it is best to only have one Diamond Goby per tank.

Compatible and Incompatible Tank Mates for Diamond Goby

A Diamond Goby is usually part of an aquarium’s cleanup crew. Let’s look at some other fish they might be paired with.

Diamond Goby and Pistol Shrimp

They will coexist but Diamond Goby will not pair with the Pistol Shrimp as is seen with some other Goby varieties.

Diamond Goby and Yellow Watchman

Diamond Goby and Yellow Watchman will usually be fine as long as they have a larger tank with enough room to have separate burrows. This can be a problematic paring so be cautious.

Diamond Goby and Lawnmower Blenny

Diamond Goby and Lawnmower Blenny will usually get along in the same aquarium. They tend to stay out of each others way: Diamond Goby in the sand and Lawnmower Blenny on the rocks.

Diamond Goby and Firefish

Diamond Goby and Firefish usually keep to themselves in an aquarium and should get along fine.

Diamond Goby and Mandarin

Diamond Goby and Mandarin will get along but they both eat copepods. Make sure your have a refugium or other method for supplying enough pods for both fish.

Diamond Goby and Engineer Goby

Engineer Goby get along with most other fish, including the Diamond Goby. Engineer Goby don’t need live food, unlike Diamond Goby. But they can eat copepods so ensure enough supply for both fish.

Where can I find Diamond Goby for sale?

Diamond Gobies are readily available in fish stores and online. They usually sell for between $30 USD and $50 USD.