Port Blair, May 13: Ornamental fish keeping is a popular hobby among the enthusiasts in which, attractive colourful fishes are kept as pets in confined spaces of an aquarium which serves as the aesthetic beauty by reducing stress and anxiety with mind relaxation to the aquarium keeper. During the pandemic lockdown, the time spent on management and maintenance of aquariums may provide an additional relief to the enthusiasts. Fishes with attractive colour pattern, swimming behavior and more resistant to captivity stress are considered as good candidate species. The commonly kept freshwater ornamental fish species include gold fish, tetra, guppy, molly, gourami, catfish, platy, zebra fish, loach, cichlid, fighter, barb, spiny eel and snakehead.
Fish health status mainly depends on the overall management of its environment. Hence, it is essential to manage the health of aquarium fishes by following the better management practices such as maintaining the optimum stocking density, good water quality, adequate nutrition, avoiding stress and preventing the introduction of pathogens. Feed is one of the major inputs that decide the health of fish as well as the culture system. The non-availability of specialized aquarium fish feeds in the light of pandemic lockdown can be managed by making the home-made standard maintenance feed with 20-25% of crude protein and 3-5% of lipid content. The standard maintenance feed can be prepared with our simple household resources. For example, to prepare one kg of feed, 400 gram of rice/ wheat (energy source), 600 gram of any dal/ grams (protein source), 50 gram of any of the colour enhancing miscellaneous additives (spinach, lettuce, carrot, beetroot, moringa leaves, marigold petals, turmeric, banana, papaya and yeast powder) may be mixed with 20 ml of any cooking oil. The feed preparation consists of the following steps such as grinding of all the required solid ingredients followed by sieving, mixing (mix the powdered ingredients with oil and water to make as dough), cooking (5 minutes using pressure cooker), pelleting (use hand press machine to make pellets from the cooked dough), drying the pellets (under fan or sunlight), crumbling (crumble by hand as per required particle size) and storing (in air tight containers). Apart from feed, there are chances of disease outbreaks in the ornamental fishes due to improper management. The following table provides the detailed information on the common diseases observed in freshwater ornamental fishes and its possible management measures.
Common freshwater aquarium fish diseases and its possible management measures
S. No. Name of the disease Causative agent Clinical signs Management measures
1. Fin and tail rot Aeromonas sp. and Pseudomonas sp. • Whitish margin of fins.
• Putrefaction of fins.
• Reddish areas at the base of fins. Mix terramycin at 100 mg/ kg of fish feed.
2. Dropsy Aeromonas hydrophila • Distended abdomen.
• Scale protrusion.
• Mild ulceration. Dip treatment in potassium permanganate (5 mg/ litre of water) for 2 minutes.
3. White spot disease or Ichthyophthirias is Ichthyophthirius multifilis • Parasites are visible as white spots on skin, gills and fins.
• Erratic swimming. Bath treatment with sodium chloride (common salt) solution for 7 days or more.
4. Lernaeasis or Anchor worm infestation Lernaea sp. • Emaciation.
• Inflammation and necrosis at the site of attachment.
• Small haemorrhagic spots. Permanent bath treatment in dipterex at 0.25 – 0.50 mg/ litre.
Bath treatment in sodium chloride (8 – 10 g/ litre of water) for 3 minutes.
5. Argulosis or Fish lice infestation Argulus sp. • Parasites are visible as a small button like structure on the body surface.
• Haemorrhagic ulcerative lesions around the bite wounds. Prolonged bath treatment in trichlorphon at 0.2 mg/ litre for 24 hours.
Prolonged dip treatment in sodium chloride (50 g/ litre of water).
6. Cotton wool disease or Saprolegniasis Saprolegnia parasitica • Cotton wool like outgrowth over injury site and haemorrhage. Long term bath treatment in 3 mg/ litre of methylene blue.
Bath treatment in potassium permanganate (160 mg/ litre of water) for 5 days.
