Your first saltwater aquarium: Step by step guide
Buy and assemble all the equipment
Equipment you will need
- A 120 litre 4 foot tank. This is a basic minimum size.
- Buy a hood with a normal lighting system.
- You will also need a protein skimmer,
- An external power filter,
- 300w heater,
- A thermometer and hydrometer to measure the salinity,
A marine water test kit
- Bag of seawater salt mix
- Natural coral sand
- Fish tank stand.
Inhabitants for your saltwater fish tank
- 10 kilos of live rock
- 1kg Live coral sand
- 10 margarita or asteria snails
- 2 hermit crabs blue or red-legged
- Some hardy peaceful fish species
Find out more about live rock and live sand here.
Preparing your first saltwater fish tank
Put together your stand and aquarium. Wash the inside of the glass with warm water. Never use any chemicals or soaps. If there are any stubborn stains then use white vinegar and a razor blade to scrape the stain. Rinse any white vinegar with tap water. Remove water with a siphon hose. Paint the rear glass in black, blue or marine or apply a stick on background.
With the tank empty move the stand and tank around the room until you find a location you are happy with. You can use a spirit level to adjust the levelness of the aquarium. If the aquarium doesn’t sit level then you can use thin flat pieces of plastic or wood to raise the leg that is lower. Once the aquarium is sitting level then you can then fill with water. Once the aquarium is 95% full then again check the aquarium for levelnbess. If the aquarium is not level then you will have to remove all the water and adjust the levelness again before re-adding water.
Once the tank is 95% full of water and level then you have to wait 24 hours to see if any slow leaks occur. If there are no signs of any leaks then install the filter, heater and protein skimmer. Set the heater to 76 Fahrenheit.
Plug in all the equipment and switch on everything. Leave everything running overnight. The next day check the temperature to be 76F. If the temperature is out then you have to adjust the thermostat.
How to get the salinity right for your saltwater aquarium
Calculate the volume of your aquarium then add your sea salt mix according to the recommended amount on the bag of your mix. If you wait another 4 hours your salt will have completely dissolved in the water. You can then check the salinity of the water with your hydrometer. The reading should be between 1.022 to 1.024 when the temperature is 76F. If it is less then you can adjust by adding a little sea salt mix. If it is more then you can reduce it by adding a little fresh water. Thenm wait a further 4 hours before testing again. When you achieved your ideal density use a black marker to mark out the water level in a hidden part of the glass. This mark will be your guide to the level of water before any evaporation. Topping up back to this level should get you back to the correct salinity.
Now test the water’s ph. It should read 8.2-8.3ph or close to this. If it is far from this then you’ve done something wrong somewhere or your hydrometer or thermometer is wrong. Fix the problem by changing your hydrometer or thermometer and make adjustments. If there is still a misreading then you will have to switch everything off and remove all the water and start again with the water mix.
Adding live rock to your saltwater aquarium
When the water is just right you then need to start adding your pieces of live rock. Start with the larger pieces first. Move the rock about to create a pleasant aquascape. Test each piece is stable by prodding and adjusting into a settled position.
Place the bigger, heavier pieces directly on the glass. These should be arranged in a long semi circle along the sides and back. Leave gaps in between the individual pieces of live rock for your fish to swim through. Place the smaller pieces of rock in front of or even on the larger pieces again making sure that the whole setup is table. Use the live rock to hide the heater and protein skimmer behind.
Adding coral sand to your saltwater aquarium
You should clean your sand before you put it in the aquarium. All you need to do is rinse it thoroughly in a bucket of water by running the water through a bucket of some sand. Do it in small batches of sand and swirl the sand round until the water runs clear. Remove the water from the backet and put the sand into the aquarium all along the floor of the aquarium around the live rock.
Once the sand has been added the average level should be 2 inches deep. Then take your 1kg of live sand and spread it evenly over the other sand. Do not wash the live sand. It should contain beneficial bacteria and life forms which you risk killing by washing with tap water.
Check all your water measurements again such as ph, salinity and temperature. Adjust if necessary.
Adding background creatures to your saltwater aquarium
After a week add your first creatures. Remember your filter, heater and skimmer should be running continuously throughout this time. Add your snails and hermit crabs. Algae eating species are recommended to clean up any algal blooms that usually break out in new saltwater aquariums. You should not just throw your snails or crabs directly into the water but float the bags in the water for 15 minutes then add some aquarium water to the bag slowly over ten minutes before releasing them into the aquarium.
Feed the snails and crabs with tiny amounts of fish food as a top up to the algae that the snails and crabs may eat, which may be insufficient for their needs.
Adding your first fish to your saltwater aquarium
More on clownfish types
More about clownfish
More on Damselfish types
Some experts recommend adding a couple of damsel fish as your first fish because they are a tough fish and can cope with the conditions while your aquarium water is cycling. While this is true I recommend an alternative to damsels as a first fish such as tank bred clownfish because damsels can be aggressive to future fish additions. You can start off with just a couple of clown fish to add colour and interest to your tank.
During this time your aquarium filter and live rock will be cycling by developing a colony of bacteria that can digest fish and other creature waste products turning it into less harmful nitrate. This process can take anything from 4-8 weeks. During this time there will be an excess of ammonia and nitrite which are harmful to your fish and other creatures.
Complete your saltwater reef aquarium set up
After your first fish have settled in and looking healthy and happy you can start adding some invertebrates and a few other fish. Add hardy species of anemone. A good choice of anemone are feather dusters.
Fish to consider at this point will be wrasses, dottybacks and banggai cardinal fish. Try wherever possible to buy tank bred fish as these are fish that have adapted to life in the aquarium and should prove better survivors in your saltwater tank. Add fish at a rate of 1 or 2 a week. When you add new fish keep a close eye on them and make sure the newly added fish start feeding within 2 or 3 days. Also check the nitrite and ammonia levels daily. Stop adding new fish if the readings rise.
Some fish and other creatures to absolutely avoid as a beginner are: seahorses, octopuses, angelfish, clams, scorpionfish, and damsels.
When you have a settled tank and have introduced all the fish and other creatures for your aquarium then you can reduce the water testing to once a week.
Now you can sit back and enjoy your own piece of the ocean in your living room. However, you still need to keep checking all your water parameters once a week at least or when something doesn’t look right with any of the inhabitants.