Choosing Marine Fish as a Pet

Marine fish are fish that need a saltwater habitat in order to survive. Keeping marine fish does require a little skill though. Their habitat needs to be carefully managed; so those thinking of keeping marine fish are recommended to do so only when they have gained some experience keeping tropical species.

Popular Species

  • Clownfish
  • Tangs
  • Dwarf Angels
  • Blennies/Gobys
  • Butterfly fish
  • Damsels
  • Puffers

Setting Up Your Marine Tank

Setting up a marine fish tank will take a little time and a lot of patience. It can be really tempting to buy your aquarium, hurry home and add your new fish to it straight away; but this will only lead to your fish feeling stressed which will then likely kill them. Your new fish need a particular environment in which to thrive; so setting up your fish tank correctly is essential to ensure their long term health and well-being.

Saltwater tanks do need a little more time than freshwater tanks; due to the salt adding a layer of complexity to their maintenance; but if you follow these simple steps, they will help you on your way to building a healthy marine tank.

Because of its extra complexity, it is recommended that you have some experience keeping tropical fish before you begin keeping marines.

Set Up The Tank:

  1. Position your new tank and stand in its permanent location
  2. Wash out the tank with water only – do not use detergents or bleach
  3. Install your heater, filter, protein skimmer and any other equipment following the directions on the pack. Do not switch on the power at this stage!
  4. Add your pre-mixed saltwater to the tank. Saltwater is available from Petmania stores that stock marine fish so your in-store fish expert can help you with this.
  5. Turn on the tank and allow the water to circulate for 1-2 days

Cure Your Live Rock and Cycling Your Tank

  1. After 1-2 days, remove some of the water from your tank and add your live rock. Place it in the centre of the tank and direct the power-heads in your tank towards it. This will remove debris from the rock
  2. After 2-3 days, wearing a pair of rubber gloves to protect your hands, clean the rock in the water using an old toothbrush to remove any dead or dying organisms
  3. Siphon the debris from your tank and replace with fresh, clean salt water
  4. Repeat this process until your water tests indicate that your tank has cycled with 0 ppm ammonia, 0 ppm nitrites and a nitrates reading of 20 ppm or below.

Adding Sand

When your tank has cycled, it is time to add the sand.

  1. Turn off the power in your tank
  2. Drain some of the saltwater from your tank to allow for the sand you are about to add
  3. Mix your sand with clean saltwater in a bucket to wash it. Allowing it to settle, remove any debris that rises to the top of the bucket
  4. Drain some of the saltwater from the bucket and using a ladle or similar, transfer the sand from the bucket into your tank
  5. Turn the tank back on, directing one of the power-heads towards your live rock to remove any sand that may fall onto it as you add it to the tank
  6. Allow your tank to settle for a few days before carrying out a full set of water tests. Ideally your water should read as:
    • Temperature 24C – 27C
    • Specific Gravity 1.020 – 1.024
    • pH 8.0 – 8.4
    • Ammonia 0
    • Nitrite 0
    • Nitrate 20ppm or less (especially for invertebrates)
    • Carbonate Hardness 7-10dKH

Choosing the Right Fish

When choosing your fish you need to take into account how they live in their natural habitat, and their natural personalities.

Some fish species are recognised as being peaceful while others can be a little aggressive or very aggressive. In addition, some species prefer to live alone; while others are schooling fish which means they prefer to live in larger groups of the same species.

Use our Compatibility Chart to help you choose the right fish to live together happily in your tank.


Adding Fish to Your Tank

To prevent the balance of chemicals in your tank from spiking and causing illness or killing your new fish; it is recommended that you only add a few new fish at a time to the new tank. The capacity of your tank will be determined by its size, the type of fish that you want to keep, and the amount of live plants that you may have in your fish tank. Our fish experts are on hand to help you determine how many and when you can introduce them to your tank.

Acclimatisation Procedures

When introducing new fish to your fish tank; you will need to allow the fish to acclimatise to its new environment slowly. Because of their sensitivity to pH, specific gravity and changes in water chemistry, marine fish and invertebrates need a slightly different acclimatisation procedure than freshwater fish. By following these simple steps you will be helping your fish to settle into their new home.

  1. Gently empty the contents of your fish bag (including the fish) into a clean bucket
  2. Add 1 cup of water from your fish tank directly into the bucket
  3. Repeat step 2 every ten minutes for an hour
  4. After an hour, your fish will be ready to be added to your new tank, so using a net, gently place your fish in
  5. Do not feed your fish on their first day in your tank. Instead, allow them 24 hours to settle in.

Take Me Home Checklist

If you are thinking of getting a marine fish tank, you will need the following equipment. Because keeping marine fish can be quite complicated, it is recommended that new fish keepers don’t launch themselves straight into keeping marine fish.

Our OATA trained fish experts are on hand instore to help you to choose the right equipment and are delighted to assist you in setting up and maintaining your fish tank. In addition, our Aquatics Manager has been keeping marine fish for many years and is available to assist you to those queries that require further exploration.

  • Marine Tank
  • Live-Rock
  • Sand
  • Ready mixed Saltwater @ 1.023
  • Heater
  • Thermometer
  • Protein Skimmer (tanks over 100L)
  • Lighting > For fish-blue and white light ; For corals 1 watt per litre
  • Food
  • Refractometer to measure salt level

Remember – you will need to have your fish tank set up and cycling for at least 7 days before you add your new fish.