Bolivian ram

Quick facts

Adult size

8 cm

Lifespan

can live up to 6 years; much hardier than German rams; routinely reaches 4-6 years

Tank zone

bottom

Temperament

peaceful

Difficulty

beginner

Water parameters

Temperature

22–27°C

pH

6.0 to 7.5

Hardness

2 to 14 dGH

Tank requirements

Minimum volume

110 L

Minimum length

75 cm

Flow

low

Lighting

dim preferred

Substrate

sand

Driftwood

preferred

Hiding spots

needed

Feeding

Diet: omnivore, feeds primarily at the bottom.

Omnivore that feeds on the bottom and in the lower midwater column. Sinking pellets, frozen bloodworm, frozen brine shrimp, frozen daphnia, live blackworms, and live baby brine shrimp. Accepts dry food readily. Not a picky eater. Sifts through the substrate for food, picking up mouthfuls of sand and expelling it through the gills. Feed twice daily. Live food enhances coloring and conditions breeding pairs.

Compatibility

• The hardy alternative to the German blue ram. Bolivian rams tolerate the temperature range of a normal tropical community (23–26°C) instead of requiring the 28–30°C that blue rams need. This makes them compatible with a much wider range of tankmates.
• Peaceful dwarf cichlid that coexists with small community fish. Mild territorial behavior around their preferred resting spot, but nothing that threatens other species. Much calmer than most Apistogramma species.
• Good with tetras, rasboras, corydoras (especially sterbai and bronze), otocinclus, and shrimp. Adult cherry shrimp are usually ignored; shrimplets are occasionally eaten.
• Pairs share territory defense during breeding but the aggression is restrained compared to kribensis or convicts. Breeding pairs in a community tank cause minor disturbance, not chaos.

Habitat

Native to the upper Rio Madeira and Rio Mamore systems in Bolivia and Brazil. Found in slow-moving rivers and streams over sandy substrates with scattered rocks and leaf litter. The habitat is warmer and harder-watered than the range of Mikrogeophagus ramirezi (German blue ram), which explains the Bolivian ram's tolerance for cooler, harder water. Adults reach 8 cm; males are larger and develop extended dorsal fin rays and more intense coloring than females. The body is olive-yellow with a bluish sheen, red-edged fins, and a dark spot on the flank. Not as visually flashy as the German blue ram, but the trade-off is dramatically better health and longevity. Bolivian rams live 4-6 years in standard community conditions, while German blue rams often die within 12-18 months from the combined effects of inbreeding, hormone treatment, and temperature sensitivity. The species entered the hobby trade in the 1980s and has been commercially bred since then.

Breeding

Substrate spawner that deposits eggs on a flat rock, piece of driftwood, or in a shallow pit dug in the sand. Both parents share egg-tending duties. Clutch size is 100-200 eggs. Eggs hatch in 3-4 days. Fry are moved to a pit by the parents, who guard them attentively. Free-swimming fry eat baby brine shrimp and microworms. Parental care lasts 3-4 weeks. The pair may eat the first few batches of eggs or fry, which is normal for young cichlids learning to parent. By the third or fourth brood, most pairs are reliable parents. Breeding doesn't require special conditions beyond a flat surface and a reasonably peaceful tank. The species is easier to breed than German blue rams because it's not as fragile or temperature-sensitive. A compatible pair in a 75 L tank will usually spawn within a few months of being established.

Common problems

Hexamita (hole-in-the-head) occurs occasionally, especially on monotonous dry-food diets. Treat with metronidazole and improve dietary variety. Internal parasites from farm-bred stock can cause wasting; treat with praziquantel. The most common issue isn't medical but a failure of expectations: keepers expecting German-blue-ram-level color intensity are disappointed by the more subdued appearance of the Bolivian ram. The visual appeal is different, not lesser. What you give up in showiness, you gain in a fish that actually lives more than a year and doesn't keel over when the heater fails. Aggression during breeding is mild but can still stress very timid bottom-dwellers like pygmy corys.

Bioload

Bioload coefficient: 2.4 (larger than German ram with more active substrate sifting; moderate waste output).

Bioload coefficients are calibrated against the neon tetra as the anchor (1.0). See the methodology page for the formula and how each value was derived.

Further reading

• How to cycle a fish tank
• Stocking ideas by tank size