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Jack Dempsey

By The Aquarium Calculators Editorial Team ·

Rocio octofasciata

Complete Jack Dempsey care guide covering omnivore diet requirements, aggressive temperament, minimum 55 Gallons tank setup, and compatible freshwater tankmates. Difficulty: Advanced.

Jack Dempsey

Quick Answer

Jack Dempsey (Rocio octofasciata) is a captivating and highly sought-after freshwater species. It requires a minimum 55 Gallons aquarium with a pH of 6.5 - 7.5 and temperature range of 22-26°C. As a omnivore with aggressive tendencies, careful tankmate selection is essential.

Intro

Jack Dempsey (Rocio octofasciata) is a captivating and highly sought-after freshwater species. Known for their aggressive nature and distinct appearance, they occupy the middle levels of the aquarium and bring dynamic energy to any setup.

Setup

Jack Dempsey requires a stable, well-filtered aquarium of at least 55 gallons. They thrive best with moderate water movement and a reliable heater to maintain temperatures around 22-26°C. Ensure pH levels remain consistent between 6.5 - 7.5 to prevent stress and support long-term health.

Feeding

As a omnivore, the Jack Dempsey is not a picky eater. They should be fed a high-quality base of flakes, sinking pellets, or wafers. Periodic supplementation with frozen or live foods, such as bloodworms or brine shrimp, will boost their health and colors.

Compatibility

Jack Dempsey has a aggressive temperament. They are compatible with other fish of similar sizes and temperaments. Avoid placing them with aggressive species or tankmates they are listed as incompatible with, such as: neon tetra, cardinal tetra, guppy, corydoras, molly, platy.

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Tank Position
Middle
Water Temp
22-26°C
Adult Size
See profile
Water pH
6.5 - 7.5

Species Characteristics

Adult Size
Lifespan
Growth Rate
moderate
Tank Compatibility
Community compatible
Indoor Aquarium
Yes

Water Parameters

Water Temperature
Humidity
Water pH

Tank Lighting

Tank Lighting
Standard lighting
Light Hours
N/A
Intensity
moderate

Feeding & Diet

Diet Type
Diet: Omnivore
Feeding Schedule
N/A
Live Food Options
N/A

Continue Learning

Recommended Tools

Fish Compatibility Calculator fish compatibility

Health & Disease

Ich (White Spot Disease) common disease • all fish

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Understanding pH in Aquariums water parameters • ph

Similar Species

African Butterflyfish Care Guide: Tank Size & Diet semanticSimilarity African Cichlid Care Guide: Tank Size & Tank Mates semanticSimilarity Bala Shark Care Guide: Tank Size & Tank Mates semanticSimilarity

Frequently Asked Questions

How many Jack Dempseys should be kept together?
Keep only one per tank, or a confirmed male-female pair in a tank of at least 75 gallons (284 liters) with a footprint of 48x18 inches (120x45 cm). Jack Dempseys (Rocio octofasciata) are large, aggressive Central American cichlids; two males in any sized tank fight to severe injury or death. A bonded pair requires 100+ gallons with multiple caves and visual barriers. For a single fish, 55 gallons (208 liters) is adequate. Provide at least 3 caves (clay pots, rock piles) and robust driftwood. Avoid with smaller fish (under 3 inches). Use a tight-fitting lid.
What are the exact water parameters for Jack Dempseys?
Target pH 6.5 - 7.5, General Hardness 5 - 15 dGH, Carbonate Hardness 4 - 12 dKH, Total Dissolved Solids 150 - 400 ppm, Electrical Conductivity 300 - 800 μS/cm, and temperature 72°F - 80°F (22°C - 27°C). They require large aquariums with robust filtration (10x turnover) to handle waste. Maintain nitrates below 20 ppm with weekly 30% water changes. Use a canister filter rated for 2x tank volume. Provide sand or fine gravel substrate; they dig. Avoid sharp decorations.
What is the dietary and medication protocol for Jack Dempseys?
They are robust carnivores requiring 50% protein, 15% fat, 35% plant matter. Feed premium cichlid pellets (Hikari Gold), krill, bloodworms, earthworms, and frozen silversides twice daily. Offer spirulina wafers and blanched peas weekly. Avoid fatty foods (beef heart). Medication alert: Tolerate copper (0.2 mg/L) and formalin. Praziquantel is safe. Salt baths up to 5 ppt treat external parasites. Quarantine with metronidazole (5 mg/L) for 10 days to treat hexamita.
How to breed Jack Dempseys with environmental triggers?
Condition a bonded pair with live earthworms and krill for 3 weeks. Raise temperature to 80°F (27°C) and perform 30% water change with slightly cooler (72°F/22°C) water. Provide a flat slate or clay pot. The pair cleans the site; female lays 300-500 eggs. Both parents guard and fan eggs. Eggs hatch in 72-96 hours at 75°F (24°C). Wrigglers become free-swimming in 7-10 days. Feed crushed flakes, baby brine shrimp, and microworms. Remove parents if they become aggressive, but they are typically good parents. Frequent water changes (30% daily) are critical.

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