How do you care for coldwater fish?

In this article we will discuss cold water fish care.We will also discuss other requirements like tank set-up,water parameters,diet,different methods of care and health conditions.

Overview

In this blog 

  • How do you care for coldwater fish?
  • What are the best coldwater fish for home aquariums?
  • Tank setup for coldwater fish
  • What are the methods to care for a coldwater fish?
  • Coldwater fish diet
  • Coldwater fish disease and health conditions
  • Daily care and bi-weekly care tips
  • Summary
  • Frequently asked questions.

How do you care for coldwater fish?

In terms of aquariums,coldwater fish are those species that don’t require a heater in their aquarium to maintain the temperatures.

Some coldwater species are easy to care for and some need extra attention. But most of them need proper tank management to thrive well in aquarium settings.

What are the best coldwater fish for home aquariums?

  • Bloodfin tetra
  • Rosy barbs
  • Gold barb
  • Two-spot barb
  • Buenos aires tetra
  • Guppies
  • Hilstream loach
  • Celestial pearl danio 
  • Weather loach
  • White cloud mountain minnow
  • Zebra danio

Tank setup for coldwater fish

Tank size for coldwater fish

Most of the coldwater fish need a bigger and spacious tank because they tend to grow faster and fitting them in smaller tanks or normal size tanks won’t be a good idea.

It would be better to keep them either in bigger spacious tanks or outdoor ponds.

  • Bloodfin tetra occupies the surface levels of the tank and they require a tank size of 15 gallons or more.
  • Rosy barbs- the optimal tank size for a community fish like rosy barbs is 20-30 gallons.They thrive well in elongated tanks.
  • Gold barbs need a minimum tank size of 20 gallons or more as they live in schools.They need 3 gallons of space per gold barb.
  • Buenos Aires tetra requires a tank size of 30 gallons and they occupy the middle region of the tank.
  • The ideal tank size for guppies is 40 gallons because they grow very rapidly.Irrespective of their small size they require bigger and spacious tanks.
  • The ideal tank size for hillstream loaches is 50 gallons.
  • Weather loaches need a minimum tank size of 20 gallons.
  • White cloud mountain minnows need a minimum tank size of 15 gallons.
  • Zebra danio occupies all the levels of the tanks and need a minimum tank size of 10 gallons. 

Light intensity for coldwater fish

Coldwater fish don’t require direct sunlight.Standard aquarium lights will be sufficient for them.

Make sure you are not adding bright lights in their indoor tanks because bright lights can increase the amount of heat in the tank which can stress them.

Substrate and decors for coldwater fish

Substrate requirements also vary from species to species because some are bottom feeders,some are surface feeders and some occupy the middle regions of the tank.

  • A soft sandy substrate,dark or light coloured is preferred
  • A rough substrate may hurt bottom feeders,so avoid using rough substrate in their tanks

Water parameters for coldwater fish

Water pH- Different species of coldwater species require different pH and degree of water hardness in their tank.

Some coldwater fish are very sensitive to ammonia pollution,so it’s very important to keep their levels in check by maintaining pristine water conditions.

  • pH testing kit is very important for maintaining a stable pH in coldwater fish tanks.
  • Rosy barbs can thrive well in the pH range between 6 to 8 and water hardness between 5-19 dGH.
  • Bloodfin tetras do well in pH between 6 to 8.They require both hard and soft water and an intermediate degree of water hardness i.e 3-12 dGH.
  • Gold barbs do well in pH between 6 to 8 and need a water hardness upto 10 dGH.
  • Buenos Aires tetra do well in a pH between 5.5 to 8.5 and mostly neutral pH is best for them.They need a water hardness between 12-35 dGH.
  • Guppies do well in pH between 6.8 to 7.8 and water hardness between 8-12 dGH.
  • They are very sensitive to ammonia pollution, so it’s very important to keep the levels of nitrates 10 ppm and levels of ammonia and nitrite 0ppm in their tanks.
  • Hilstream loaches do well in pH between 6.5 to 7.5 and a medium water hardness will be best for them.
  • Celestial pearl danio do well in pH between 6.5 to 7.5 and water hardness between 2-10 dKH.
  • Weather loaches do well in pH range between 6.0-8.0 and water hardness ranges between 3-10 dKH.
  • White cloud mountain minnows do well in pH between 6.0-7.0 and water hardness between 5-20 dKh.
  • Zebra danio can thrive well in the pH range between 6.8-7.5 and water hardness of 50-100 mg/l calcium carbonate.

Water temperature  for coldwater fish

  • Ideal temperature for coldwater fish tanks may vary between-61F to 75F, depending upon the species.
  • Coldwater fish aquariums should be kept away from heaters and direct sunlight.
  • Bloodfin tetra can tolerate temperatures lower than 60F.
  • Rosy barbs can tolerate temperatures either 60F or even lower.
  • Gold barbs do well in a temperature range between 64-75F.
  • Buenos Aires tetra requires a temperature range between 64F-82F.
  • Guppies do well in a temperature range between 72F-82F.
  • Hilstream loaches do well in temperature range between 68F-75F.
  • Celestial pearl danio do well in temperature range between 73F-79F.
  • Weather loaches do well in the temperature range between 65F-75F.
  • White cloud mountain minnows require a temperature range between 60F-72F.
  • Zebra danio can thrive well in the temperature range between 64-74F.

List of coldwater aquarium fish that don’t require a aquarium heater

  • Sunset variatus platy
  • Celestial pearl danio
  • Rainbow shiner
  • Hillstream loach
  • Endler’s livebearer
  • Clown killifish
  • Cherry shrimp
  • Dojo loach

Water filters-Filters are very important in some of the coldwater fish tanks to maintain tank pollutants,as some coldwater fish produce large amounts of biological waste which inturn increases ammonia spikes in the tank.

So a filter is very important to maintain the nitrogen cycle by producing beneficial bacteria and it also circulates the tanks.

Goldfish in particular are messy eaters and produce huge amounts of waste so it’s a must for such coldwater to have a big filter attached in their tanks. 

Air pumps for coldwater fish

Goldfish have higher oxygen demand and aeration so air pumps or air stones are much needed in their tanks.

Tank plants for coldwater fish

Dense vegetation with live and floating plants are best for coldwater fish tanks as it replicates their natural habitat.

  • Guppy grass 
  • Hornwort
  • Dwarf hygro
  • Stemmed plants
  • Artificial or fake plants

What are the methods to care for a coldwater fish?

  • Tank method
  • Pond method

How to maintain cold water fish in tanks?

  • Neon tetras and Danios can be easily maintained in indoor tanks.
  • Normal tank setups like bigger to medium sized tanks, gravels,water testing kits,properly cycled tanks,water filter, air pumps, pH meter,gravel siphon,algae scraper,hydrometer and standard aquarium lighting.

How to maintain cold water fish in ponds?

  • Coldwater fish are mostly bigger in size and due to their size they are more suitable for outdoor ponds.
  • The most common coldwater fish are goldfish and koi,which are suitable for outdoor ponds.
  • They grow very rapidly in size and it won’t be easier to maintain them in indoor tanks,so outdoor ponds are best for them.
  • For an outdoor setting,you need aquatic plants, and some pre-treated tree logs.
  • You can add snails to remove algae from the pond or remove plants which are polluting the pond by harboring algae on them.

Coldwater fish diet

Diet for coldwater fish may vary from species to species,here i am listing down some of the common coldwater fish food:

  • Granulated food/pellets/flakes
  • Vegetables like spinach,cucumber, peas
  • Vegetable supplements like spirulina flake or spirulina cubes
  • Live and frozen food like baby brine shrimp,daphnia, cyclops, bloodworm,planktons,prawns,krills,mussels
  • Freeze dried food-mysis shrimp, tubifex worms, freeze-dried cubes.
  • Some even munch on aquatic plants like hornwort

Feeding frequency for coldwater fish

  • Some coldwater fish can live without water for 1 weeks.
  • Small coldwater fish can be fed small portions 2-3 times a day.
  • Bigger and predatory coldwater fish should be fed once a day.

Coldwater fish disease and health conditions

  • White spot disease
  • Parasitic disease (marine ich,skin flukes and worms)
  • Bacterial coldwater disease-It occurs when the temperature is below 16 degrees.
  • Fin-rot-Fin decaying disease.
  • Gill burns due to ammonia spikes in goldfish tanks.
  • Overfeeding can lead to obesity.

Daily care and bi-weekly care tips

Daily care tips for coldwater fish

  • Regular tank maintenance is mandatory.
  • Clean the gravels using a gravel siphon everyday to remove uneaten food and debris from the tank.
  • Algae should be removed daily to avoid water contamination.
  • Nitrates and phosphates levels should be checked daily.
  • Always keep the indoor tank and outdoor pond free from chemicals.

Bi-weekly care tips for coldwater fish

  • Whole coldwater fish tank should be cleaned once every 15 days.
  • 10-15 % of water should be changed weekly.
  • Water testing kit should be used weekly once to maintain water parameters.
  • Always quarantine new fish for weeks before adding them to the main tank.
  • Live food should be quarantined too for 2 weeks before feeding them.
  • Separate sick tank mates to a separate tank or pond to avoid infection from spreading to others.

Summary

  • Most of the coldwater species require bigger and spacious tanks or an outdoor pond to house them as they grow very rapidly.
  • Oxygenated tanks are very important for some coldwater species.
  • Coldwater fish are compatible with other coldwater species in most cases.
  • Coldwater fish rarely require aquarium heaters in their tanks.
  • Coldwater fish thrive well in a fully cycled tank free of organic pollutants.
  • Coldwater fish are recommended for both newcomer and experienced fishkeepers.

Frequently asked questions

What are the best coldwater fish for beginners?

Best coldwater fish for beginners are white cloud mountain minnows and bloodfin tetras.

What is the lifespan of coldwater fish in aquarium settings?

Coldwater fish lifespan may vary depending upon the species and the type of care they are getting in aquarium conditions.In general they can live up to 5 years.

Which coldwater fish can survive in very low temperatures?

Pond loaches,koi and goldfish can survive in very low temperatures among other coldwater fish.

Reference

https://www.petsathome.com/shop/en/pets/advice/fish-care-advice/cold-water-fish-advice
https://www.thesprucepets.com/what-fish-species-are-coldwater-1380965