The magnificent Stiphodon sp. undio blue is a captivating species of freshwater goby that brings wellness and elegance to a planted aquarium. Its male specimens display a striking electric-blue lateral stripe and shimmering body when fully comfortable, while females are more subtly coloured yet equally charming. Though small in stature, their behaviour, coloration and habitat demands make them a rewarding choice for those who are willing to give them the conditions they deserve.

Habitat & Natural Behaviour

Native to clear, fast-flowing streams and rivers often in tropical island regions, this species is adapted to high-oxygen, highly moving water environments, frequently over a rocky or gravel substrate. These conditions drive their behaviour of grazing biofilm and algae on surfaces, and of using substrate and rocks for resting and territory.
In aquarium conditions, they appreciate strong water movement, elevated oxygenation and plenty of surfaces (rocks, wood, plants) where natural micro-organisms can grow for them to feed upon naturally.

Aquarium Setup & Care Instructions

Tank size & layout
While the individual fish remain small (typically under 5–6 cm long) they are best housed in a mature aquarium of at least ~80 litres. The recommendation arises because their needs for high water quality and flow are more easily met in a larger volume. Decorate the tank with smooth rocks, driftwood, and possibly some river-pebble substrate or sand. Strong water movement via a good filter, powerhead or return flow is essential.
Hardscape should include horizontal and vertical surfaces so they can cling to or rest on elevated rocks or wood. Planting is optional but valued — hardy species like Anubias barteri or Bolbitis heudelotii work well and allow natural biofilm growth.

Water parameters

• Temperature: Maintain around 24–28 °C (75–82 °F)

• pH: Preferably 6.5 to 7.5

• Hardness (gH): Generally in the 5–10 °d range for best comfort

• Oxygenation: Strong circulation is very important; surface agitation and supplemental aeration are beneficial.

• Maintenance: Regular water changes, careful monitoring of nitrate/nitrite levels and avoiding any sudden parameter swings will keep this species healthy.

Feeding & nutrition
In the wild, this goby grazes on biofilm, algae and microorganisms found on rocks and surfaces. In captivity you should replicate this by:

• Allowing natural algal and biofilm growth (via substrate/rocks and lighting)

• Supplementing with high-quality sinking foods rich in plant matter (e.g., spirulina wafers)

• Occasionally offering small amounts of frozen or live foods (e.g., daphnia, finely chopped bloodworm) to provide dietary variety — but avoid overfeeding with heavy meaty foods as they are adapted to a primarily vegetarian diet. 
  Ensure that when you feed, the food reaches areas where the fish forage (e.g., rock surfaces, bottom ledges) so they can access it.

Tank-mates
Because of its small size and peaceful disposition, Stiphodon sp. undio blue is compatible with other peaceful community fish of similar size – small rasboras, tetras, dwarf shrimp and other bottom dwellers are good choices. Be cautious, however, to avoid aggressive or large fish that may intimidate or out-compete them for food. Also ensure that tank mates do not stir up substrate excessively or cause parameter instability.

Behaviour & Social Notes

Generally a peaceful species, these gobies tend to thrive in groups (one male with two or more females works well) because social interaction and presence help them display their best colours and reduce stress. Juveniles and less dominant individuals may appear duller until they have settled in and grown comfortable. Healthy males will show more vivid, metallic blue or greenish stripes along the body.

Challenges & Tips for Beginners

• Water quality is paramount: Because these fish are accustomed to clear, fast-flowing water in nature, they don’t tolerate poor quality, high nitrates or low oxygen well.

• Allow biofilm/algae to develop: Don’t rush to clean away all algae; some biofilm serves as natural food.

• Strong water flow and oxygenation: A moderate-to-strong current and good filtration are key to mimicking their natural habitat.

• Stable environment before introduction: It’s best to introduce these fish only after the tank has been fully cycled, matured and stable in terms of parameters.

• Beware of mis-labelling: In the trade, many “neon blue gobies” are misidentified. Ensure you buy from reputable suppliers.

• Provide hiding/foraging spaces: Rocks, driftwood and surfaces help them feel secure and create micro-habitats for feeding.

Summary

If you’re a beginner aquarist looking to add a stunning and active species to your tank, the Stiphodon sp. undio blue represents an excellent choice — provided you are willing to invest in setting up and maintaining the correct environment. With the right care, you’ll witness a small, lively fish shimmering with vivid colour, grazing rocks and bringing life to your underwater world.