Green Uruguay Dwarf Pleco

Where they come from

Hisonotus ringueleti is a tiny loricariid from the Uruguay River basin in Uruguay and northeastern Argentina. Think shallow, sunlit creeks with grasses hanging over the edges, clear cool water, and lots of submerged plants and stones to graze on. That cooler, well-oxygenated vibe is the key to keeping them happy at home.

Setting up their tank

Give them space to graze and a steady supply of oxygen. A seasoned 15-20 gallon tank for a group is a good starting point. Fine sand or smooth gravel, rounded river stones, a couple of small driftwood branches, and a pile of leaves (oak or catappa) make them feel at home. Dense plants and mosses create extra grazing surfaces.

They appreciate a bit of current. A sponge filter plus a gentle powerhead or a canister with a spray bar works well. Keep light moderate to grow soft algae on the hardscape.

• Temperature: 68-75 F (20-24 C). They handle a slight cool-down in winter.
• pH: roughly 6.4-7.6. Aim middle and stable.
• Hardness: soft to moderately hard (2-12 dGH).
• Flow: gentle to moderate, with good surface agitation.

What to feed them

They are periphyton grazers first, everything else second. In a mature tank they spend the day rasping soft algae and biofilm off leaves, wood, and stones. You still need to feed them, especially in newer or very clean setups.

• Algae wafers and spirulina tabs (good quality, sink fast).
• Repashy Soilent Green, Super Green, or similar gel foods spread thin on rocks.
• Blanched veggies: zucchini, cucumber, green beans, spinach, squash (weight them down).
• Small protein boosts 1-2x per week: frozen daphnia, baby brine, or a tiny pinch of high-quality nano pellet. Do not overdo the protein.

How they behave and who they get along with

Peaceful and busy. They spend most of the day cruising leaves and glass, then chill on a stem or stone. They are more confident in a group, so buy at least 6.

• Great tankmates: small tetras, pencilfish, pygmy corys, ricefish, peaceful rasboras, cherry shrimp, snails.
• Usually OK: small Apistogramma if the tank is roomy and line of sight is broken up.
• Avoid: boisterous barbs and danios, big cichlids, anything that outcompetes them at feeding time.

Breeding tips

They will spawn in a settled tank if well fed. Males stay slimmer and may show more odontodes; females get round when full of eggs. Cool, fresh water changes and a bump in flow often kick things off.

They scatter a few adhesive eggs on plant leaves, moss, or glass. No parental care, and the adults might snack on eggs. Either move the eggs to a rearing box with an air stone, or pack the tank with fine-leaved plants so more survive.

• Incubation: roughly 3-5 days depending on temperature.
• First foods: biofilm, powdered spirulina, infusoria, and freshly hatched baby brine in tiny amounts.
• Filtration: sponge filter only or a pre-filtered intake so fry are not sucked in.
• Keep lots of seasoned botanicals and a bit of green fuzz around for constant grazing.

Common problems to watch for

• New imports arriving skinny: avoid fish with pinched bellies and a hollow look behind the head. Quarantine and feed heavy on greens.
• Starvation in spotless tanks: if there is no biofilm, they fade. Seed the tank and supplement daily.
• Heat and low oxygen: they stress fast in warm, stagnant water. Add surface agitation and keep temps reasonable.
• Medication sensitivity: many loricariids react badly to copper and some dyes. If you must medicate, use a hospital tank and go gentle.
• Competition for food: fast midwater fish grab everything. Target feed wafers and gels right onto the hardscape.
• Rough decor: sharp rocks can scrape their bellies. Use smooth stones and sand.