Breeding Bolivian Rams: An Easy Aquarist's Guide

Bolivian Rams (Mikrogeophagus altispinosus) are a peaceful and colourful species of cichlid, native to the freshwater systems of Bolivia and Brazil. They are a popular choice for home aquariums due to their striking colours, small size, and ease of care. They are also relatively easy to breed in captivity, making them a fun project for fish enthusiasts. In this article, we will explore the topic of breeding Bolivian Rams and provide a comprehensive guide to help you get started.

Breeding conditions

Breeding Bolivian Rams is considered a fairly easy and rewarding project. However, there are some specific conditions that need to be met for successful breeding.

Firstly, it is important to start with a group of at least four to eight juvenile fish and allow them to form breeding pairs naturally. Squabbles among the group are common but are usually harmless. It is recommended to have a spacious tank of at least 50 gallons for one pair of Bolivian Rams. The tank should be well-decorated with hiding spots, such as driftwood, rocks, and densely grown plants. Floating plants, such as watersprite, are also a good idea. In addition, a few flat rocks should be included as breeding sites, as Bolivian Rams release their eggs on flat surfaces.

The water temperature should be kept in the range of 77-83°F, with the lower end of this range being ideal for triggering spawning. The water pH should be slightly acidic, ideally below 6.8, but there are reports of successful spawning at a pH of 6.8 and above. The water hardness should be kept between 6-14 dGH.

To mimic their natural habitat, the lighting in the tank should be dim to moderate, and the water movement should be weak. Bolivian Rams prefer slow-moving waters and will need a filtration system that doesn't generate a strong flow.

Once a pair has been established, they will begin preparing their chosen area before spawning. The male will protect the breeding site, while the female will swim over the rock several times, releasing 10-200 eggs. The male will then fertilize the eggs, and both parents will fan them to keep them oxygenated and prevent fungus. After incubation, which usually takes around 60 hours, the fry will hatch and become free-swimming within 3-7 days. The parents will then relocate the fry to different parts of the tank.

It is important to note that the couple may be ready to breed again within two weeks, and they may chase away or even kill the fry from the previous batch. Therefore, the fry should be moved to their own aquarium before this happens.

Sexing Bolivian Rams

• One of the most reliable methods to sex Bolivian Rams is to examine their bellies. Females tend to have rounder bellies, while males have flatter bellies that point slightly upwards towards the breeding tube.
• The breeding tube, also known as the anal tube, is another indicator of sex. In females, the breeding tube is thicker and more prominent, while in males, it is smaller and more pointed.
• The shape of the chin can also provide clues about the sex of Bolivian Rams. Females tend to have more rounded chins, while males have less rounded or dainty chins.
• Vent sexing is considered the most accurate method to determine the sex of cichlids. It involves examining the genital papilla during spawning. The female's vent is short and blunt, while the male's vent is long and pointy. However, this method may be difficult for beginners as it requires observing the fish during spawning.
• As Bolivian Rams mature, physical differences between males and females become more pronounced. Males tend to grow larger than females and develop longer fins and more intense coloration.
• Behavioural differences can also be indicative of sex. Males tend to be more aggressive and display dominant behaviour, such as lip-locking and chasing. They also tend to stay apart from each other, occupying their own space in the tank. Females, on the other hand, are more likely to wander freely in the tank.
• When buying Bolivian Rams from a store, it is recommended to select a definite male, which is usually the most colourful and dominant fish in the tank. Then, look for another fish that seems to be associated with the male, as it is likely to be a female.
• If you plan to keep a group of Bolivian Rams, it is generally recommended to have more females than males to avoid harassment and territorial behaviour.

In summary, sexing Bolivian Rams requires a keen eye and some experience. While there are no guaranteed methods, combining physical characteristics examination, behavioural observations, and a good understanding of the species will increase the accuracy of sex determination.

Preparing a tank for breeding

Tank Size and Setup:

Bolivian Rams require a spacious tank to accommodate their active swimming behaviour. The minimum recommended tank size for a pair of Bolivian Rams is 30 gallons (113 litres). However, if you plan to have a group of these fish, it is advisable to opt for a larger tank, with an additional 5 to 10 gallons per fish. For example, a group of 4-8 Bolivian Rams would ideally be housed in a 50-gallon tank. The bigger the tank, the better, as it provides more space and stability for these active swimmers.

Water Conditions:

Bolivian Rams are native to the Amazon River and thrive in warm, soft, acidic waters. It is crucial to replicate their natural habitat as closely as possible. The water temperature should be maintained between 71-81 °F (22-27 °C), with a pH level ranging from 6.0 to 7.5. The water hardness should be between 6 to 14 dGH, with an ideal level of 10 dGH. Regular water changes, typically weekly, are essential to maintain optimal water quality and remove nitrates.

Filtration and Water Flow:

Bolivian Rams prefer minimal water flow in their tank, so choosing a filtration system that doesn't generate a strong current is crucial. External canister filters or hang-on filters are good options as they provide excellent biological filtration while allowing you to adjust the water flow to a slower rate. It is also important to monitor water parameters regularly with test kits and a thermometer to ensure stable and optimal conditions.

Tank Decorations and Plants:

The natural habitat of Bolivian Rams consists of dense vegetation, roots, submerged branches, and a muddy or sandy substrate. Replicating this environment in the tank is vital for their well-being. Use a sandy substrate and decorate it with pebbles and stones to recreate a natural look. Include flat rocks, caves, and driftwood, as these fish like to browse for food through the substrate and use flat surfaces for spawning.

Plants are not mandatory but can be added to provide additional shade and cover. Good aquatic plant options include floating plants, Java ferns, Vallisneria, Cryptocoryne, or Water Wisteria. It is important to maintain open swimming spaces while providing enough hiding spots to mimic their natural habitat and ensure their security.

Lighting:

Bolivian Rams prefer dim to moderate lighting levels. You can use floating plants to create shade, or adjust the lighting in the tank to achieve the desired effect.

Diet and Feeding:

Bolivian Rams are omnivores and will eat a variety of plant matter and small invertebrates. In the wild, they sift through the substrate for food. In the tank, offer them a combination of commercial pellets, live food, and frozen meaty foods. Bloodworms, blackworms, brine shrimp, and chopped earthworms are excellent options. Avoid flake foods, as pellets are more likely to sink to the bottom, where these bottom feeders tend to feed. Feed them several small portions throughout the day, ensuring they consume all the food to prevent water pollution.

By following these detailed instructions and providing optimal tank conditions, you will create an ideal environment for breeding Bolivian Rams, allowing them to thrive and display their captivating behaviours.

Spawning behaviour

Bolivian Rams are open spawners in their natural environment, producing around 100 eggs per spawning. Breeding them in an aquarium is more challenging.

To breed them in an aquarium, you should start with a group of four to eight juvenile fish and allow them to pair off naturally. It is not necessary to use a spawning tank, but the conditions must be right for breeding in the community tank. The tank should be spacious—at least 50 gallons for one pair of Bolivian Rams. Keep the light in the tank low and the water temperature between 77° to 82°F.

Once the conditions are right, the breeding pair will begin preparing and cleaning their chosen area before spawning. The female then swims over the nesting area a few times, laying her eggs as she goes. The male ram protects the area and drives away any fish that might attempt to eat the eggs.

Once the eggs have been deposited, the male swims over them, fertilizing them externally. Both parents then fan the eggs to keep them oxygenated and to prevent fungus from forming. The eggs usually hatch within around 60 hours, and the fry will be free-swimming within about seven days. Over the following few weeks, the parents will carefully relocate the fry to different parts of the tank.

Initially, you can feed the fry with Vinegar Eels or Shrimp Nauplii. Once the babies are around two months old, you can offer them the same diet as their parents. As the fry grow, you will need to perform daily water changes of around 30% to keep the water fresh and maintain low nitrate levels.

Raising Bolivian Ram fry

Setting Up the Tank:

• Use a spacious tank: A minimum of 30 gallons is recommended for a single adult Bolivian Ram, and you should allow for 5-10 gallons per additional fish. For breeding and raising fry, a larger tank of at least 50 gallons is ideal.
• Replicate their natural habitat: Bolivian Rams are found in lagoons, pools, and streams with dense vegetation, roots, and submerged branches. Use live plants, driftwood, and flat rocks to create hiding spots and a natural environment.
• Water conditions: Maintain a water temperature between 74°-83°F (some sources recommend 71°-81°F), a pH of 6.0-7.4 (or even lower for breeding), and a water hardness of 6-14 dGH.
• Filtration and water changes: Bolivian Rams require pristine water conditions. Use a filtration system that doesn't generate a strong flow, and perform weekly water changes to keep the water clean and remove nitrates.
• Lighting: They prefer dim to moderate lighting levels, so you can use floating plants to create shade.

Feeding and Care:

• Diet: Bolivian Rams are omnivores. Offer a varied diet, including pellets, live food (bloodworms, brine shrimp, etc.), and frozen meaty foods. They are bottom feeders, so use sinking pellets rather than flake food.
• Feeding frequency: Feed several small portions per day, providing just enough food for a few minutes. Avoid overfeeding to prevent water pollution.
• Spawning and egg care: The female will lay her eggs on a flat rock, and the male will fertilize them. The eggs will hatch within 2-3 days, and the fry will be free-swimming within a week.
• Caring for fry: After the eggs hatch, the fry will be transported to a shallow pit dug by the male. The parents will care for the fry, but they may be ready to breed again within two weeks, so it's best to move the fry to their own aquarium.
• Feeding the fry: Feed the fry with microworms, crushed spirulina flakes, or baby brine shrimp. As they grow, you can introduce newly hatched brine shrimp.
• Water changes: Perform small water changes after each feeding session to maintain water quality. Aim for daily water changes of 20%-40% to keep the water fresh and control nitrate levels.
• Tank maintenance: Remove dead and decomposing plant material to prevent water pollution. Ensure good water flow and filtration to manage organic waste, especially when first feeding the fry.

Additional Considerations:

• Tank mates: Bolivian Rams are peaceful fish, but they may view tiny fish as prey. Avoid keeping them with aggressive species. Suitable tank mates include tetras, barbs, danios, bettas, and certain types of catfish.
• Breeding triggers: There don't appear to be specific triggers for spawning. Keep a group of at least 3-4 males and females together until they naturally form breeding pairs.
• Sexing: It's challenging to determine the sex of Bolivian Rams. Males are generally larger with longer fins, and females may appear 'heavier' in the body.

By providing the right environment, diet, and care, you can successfully raise healthy Bolivian Ram fry and enjoy the beauty of these colourful fish in your aquarium.

Frequently asked questions