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How to Care for Healthy Tropical Fish

How to Care for Healthy Tropical Fish

How to Care for Tropical Fish

Caring for Tropical Fish

How to care for healthy Tropical Fish – There is more to consider about caring for tropical fish than one might at first think. This is due to their requirement for heat and the associated considerations. 

It is not possible to care for tropical fish in an outside aquarium unless very specialist heating equipment is employed.  

So first thing to consider is the aquarium:

Tropical Fish: Living Quarters

The positioning of the aquarium needs careful planning to ensure it cannot be affected to draughts or direct sunlight, or a radiator or cooling unit.  Further, it needs to be where there are no vibrations such as near doors or high traffic areas.  If placed in front of a source of natural light, like a window for example,  as it can increase the production of algae in the tank which in turn will upset the balance of the tank’s ecosystem.

The aquarium will need a filtration system.  There is a choice of three types of filter: chemical, mechanical and biological – get advice from your pet store.  Salt water tanks will also need a protein skimmer for the removal of organic residue from the water.

A Heaterstat is a heater and thermostat combined and designed to operate under water.  You set the water temperature and the heater automatically turns on when the temperature drops.  It is really important that you keep a daily overview of the temperature.  A faulty heater could result in your fish dying.  Choice of water heater is dependent upon the size of your tank – generally the rule of wattage is 5 watts per gallon.

Water temperature for freshwater tropical fish is 23-28 degrees, and saltwater fish require 24-27 degrees.  The choice of fish is key, so check.

Also a water pump is needed which, as you’d expect, pumps air into the water to assist the fish breathing.  Some suggest this isn’t necessary as the filter introduces enough oxygen, however, depends on the amount of vegetation as well as fish in the tank.

Choice of tank light will be governed by the choice of fish and whether it’s salt water and also the vegetation you have installed.  Fluorescent tubes are most commonly used as they are reasonably priced and don’t introduce heat to the water.

The tank environment must be designed with plants, rocks and ornaments to emulate the natural environment otherwise the fish may become stressed and eventually die.  A saltwater tank will need live rock – bits of naturally broken off coral – to introduce live organisms for the tank’s ecosystem.

Introducing Fish to the Aquarium

40 Beautiful Tropical Fish Pictures

You must run the aquarium for  period of 3-7 days to stabilise the environment and facilitate the removal of harmful impurities.  Introduce some good bacteria with a cycling-aid product, necessary for creating the required ecosystem.

Choice of fish should be considered carefully. Get assistance from the pet shop.  The initial few fish should be resilient fish that can withstand the high ammonia content that is likely to be present in the newly prepared tank.  Only add 3 fish a week to the ammonia levels are not affected.

When introducing a new fish, turn the tank light off, insert the bag with the new fish in, and leave there for about 30 minutes.  Then put some tank water in the bag and leave for a further 15 minutes  before netting out the fish and removing the bag.

Saltwater fish need quarantining for a period in a separate tank before introducing to the aquarium.

Feeding Tropical Fish

As with cold water fish, the amount of food needed is what will be eaten within 3-5 minutes.  Any food left floating or sinking to the bottom demonstrates over feeding which will kill the fish.

Saltwater fish may need weaning onto the new food, particularly if they’re caught fish.

High-quality frozen food along with pellets is recommended, with the frozen food fully defrosted before feeding.

Day to day tank monitoring

Each day, check the temperature of the water to ensure it is within the required range according to choice of fish.

Monitor the water on a weekly basis. The ideal water levels, according to ‘wikiHow’ are as follows:

  • pH – 6.5 – 8.2
  • Chlorine – 0.0 mg/L
  • Ammonia – 0.0 – 25 mg/L
  • Nitrite – 0.0 – 0.5 mg/L
  • Nitrate – 0-40 mg/L
  • Hardness – 100-250 mg/L
  • Alkalinity – 120-300 mg/L

For Saltwater tanks:

  • pH: 8.0 – 8.4
  • Ammonia: 0 mg/L
  • Nitrite: 0 mg/L
  • Nitrate: 20 ppm or less (especially for invertebrates)
  • Carbonate hardness: 7-10 dKH

If any of the levels are higher than they should be, remove some of the water and replace until the levels are where they need to be.

If the water ever looks cloudy, replace some of the water and check your filter is working.

For freshwater tanks, each week remove 10% of the water and replace with dechlorinated water. The replaced water needs to be at the same temperature as that already in the tank.

Monthly, remove 25% of the water and rplace with dechlorinated water – again ensure the water is at the right temperature.

For Saltwater tanks, once a month replace 20% of the water, or 5% weekly – be sure to prepare the correct saltwater solution at least a day before.


Each week, you should scrub the walls of the aquarium to remove any algae buildup. The type of pad to use is dependent upon the material for the tank’s walls. if there is a lot of algae buildup, this could indicate that the tank’s ecosystem isn’t balanced, so you’d need to check you’re not overfeeding, or have too many fish, or the tank’s getting too much natural light. Each month you should:

  • check the filter, replacing the carbon, filter cartridge and pre-rinse filter.
  • change the air stone on the water pump
  • prune any live plants in the tank to prevent over-growth and remove any dead or decaying leaves

Annually clean the pump’s impeller assembly.