How to Set Up a Marine Tank

With all of your equipment accounted for, it’s time to set up your brand new saltwater aquarium. This is a long process that will take a few weeks when done properly, particularly when you consider the time it takes to mature the tank and ensure the conditions are suitable for adding livestock, so patience is key. Before you start, we advise reading through the full step-by-step marine tank set up guide so you’re familiar with the full process before you start.

Step 1: Adding the equipment

Most of the equipment can be added to the Juwel Vision 180 Marine Aquarium at this first stage, before adding any water. This is a long step as it includes information about setting up the lighting system, protein skimmer and filter, so we’ve split it up to make it a little easier to follow.

Setting up the lighting system

Start with the lighting system, which should be unplugged from the mains, and check that your two fluorescent bulbs are correctly installed. When you purchase the Juwel Vision 180 Marine Aquarium, two marine-suitable bulbs are included, but if you’ve chosen a different aquarium make sure you have one blue bulb and one white. While these can be inserted in either position, we recommend placing the blue bulb at the front of the aquarium with the white closer to the back as this will help to bring out the colours of your fish, as well as any inverts you plan to have.

It is important to use a mixture of blue and white bulbs if you’re looking to house corals, as this helps to replicate the natural light conditions in tropical areas, taking into consideration the depth of the water where the corals will naturally live. Don’t forget that the great majority of corals depend upon photosynthesis to prosper, and that over time fluorescent tubes will fade. With this in mind you should replace them every 6 – 12 months to ensure you’re providing the optimum lighting conditions for your livestock. It is also worth noting that two fluorescent bulbs should be seen as the minimum used. If you can increase the number of tubes in the hood, or are able to fit LED lights in addition to the standard Juwel lighting, this will allow you to keep more sensitive and light dependent inverts within the aquarium.

Setting up the protein skimmer

Now that the lighting has been updated, the Tunze Doc Skimmer 9004 can be added to the aquarium. This type of protein skimmer is highly recommended for all Juwel Aquariums as it is easy to install and helps to lighten the load of cleaning maintenance. However, if you’re using a different aquarium, then we would recommend buying a protein skimmer from the same manufacturer, which you can find in our skimmer collection online.

Setting up the heater and filter

Now that you have your lighting and your protein skimmer in place you can ensure that your aquarium heater and Juwel filter are ready for operation. With purchase of the Juwel Vision 180 Marine Aquarium, the inbuilt filter comes readily fitted with five high-performance filter media that are suitable for a marine aquarium set up, all of which can be replaced when needed.

Adding the substrate

The final thing to do in this stage of the saltwater aquarium setup is to add the substrate, which will typically be live sand or crushed coral sand. How much substrate you need will depend on the size of your aquarium, but if you’re using the Juwel Vision 180, one bag will suffice. Assuming you’re using coral sand, simply rinse well before adding to the aquarium, but if you’re using a ‘live’ substrate, then don’t add this until the end of Step 2.

Step 2: Adding the water

With the majority of the equipment in place, it's time to add your water. Ideally, if you have access to RO water, use this to ensure you’re not adding any pollutants on day one. If not, and you have no nitrate or phosphate readings when testing your tap water, it’s time to fill the aquarium.

A good tip to remember when filling your marine aquarium is to keep the water level a few centimetres below the max fill level, this is because when you add the salt the water level will increase. Once filled, add a dose of dechlorinator (unless you’re using RO water) and then switch on your heater and Juwel Filter (but not the protein skimmer) which will start to warm and circulate the aquarium’s water. Doing this will also help to trap the sediment from the coral sand, which will inevitably be clouding the fish tank.

Step 3: Mixing the salt water

It’s now time to mix your first batch of seawater, which fortunately isn’t that difficult! Over time, you’ll get the hang of this, but even experts don’t get it right the first time round. You’ll also need to make sure that you get the right type of salt for your marine aquarium, as our recommendations differ depending on whether you’re setting up a coral tank or fish only tank. For coral and fish tanks, for example, we would recommend marine salts such as Red Sea Coral Pro, Aquarium Systems Reef Crystals Salt or TMC Reef Pro Salt. For a fish-only aquarium, Red Sea Marine Salt, Instant Ocean Marine Salt or Tropic Marin Marine Salt are preferable alternatives.

As a guide, 25kg of salt will mix approximately 600lts of saltwater. So for a 180lt aquarium, you’ll need approximately 7.5kgs of salt. In order to achieve the correct salinity without any water or salt wastage, try to add less salt than is needed before gradually adding more. Once you’ve added what you think is the correct quantity of salt, allow it to mix for several hours, while allowing the Juwel filter pump and heater to do their work. Something extra to note is that the salinity of seawater changes with temperature, so keep this in mind when mixing salt. Always mix it in water that is heated to the same temperature as your aquarium.

After waiting a few hours (we’d recommend overnight), it’s time to test the salinity of your water (assuming the tank is up to temperature). To do this you’ll need a refractometer, such as the D-D Solutions Refractometer. This piece of equipment is easy to use and exceptionally accurate, helping you reach your target salinity of around 1.025 quickly.

If you find the water mixed is below this level, just add more salt. If you’re over, add more freshwater – until you reach the correct level. Don’t forget it may take an hour or so for the salt to be absorbed into the water, so this process of small adjustments can take a while.

Step 4: Maturing the system

A necessary step for those using live rock in their aquariums, maturing the system ensures that the beneficial bacteria that lives within the live rock doesn’t suffer any additional damage. Adding live rock to a sterile aquarium that hasn’t been matured means exposing it to high Ammonia and Nitrite levels, and maturing the system prior to adding this helps to minimise any spikes.

Evolution Aqua Pure Reef Balance is a great product for this with clear instruction for the process. In overview, you add the specified dosage of Pure Reef Balance into the aquarium each day, and monitor the levels of ammonia and nitrite. You’ll notice that after a few days the ammonia level will increase, before it then starts to fall again. The reason this fall is that beneficial bacteria are consuming the ammonia. This drop will also cause the nitrite to increase as the bacteria that consumes the ammonia produces nitrite as a by-product. The next colony of beneficial bacteria that arrives will consume the nitrite. Again, you’ll know when they’ve arrived as the nitrite level will subside. You should only add your live rock once both ammonia and nitrite levels are zero, which may take a few weeks.

Step 5: Adding the live rock

Now that the fish tank has matured, it’s time to add the live rock. This will generally arrive in plastic bags, but not immersed in water. Take the rock pieces out of the bags and inspect them thoroughly, keeping an eye out for small crabs. If you spot any, don’t add them to the aquarium – they will be a nightmare to get rid of and will likely cause havoc. Once you’re confident you have no unwanted hitchhikers, add the rock to the system, removing water as required to stop the aquarium from overflowing.

When aquascaping, you may notice that the rock pieces have algae on one side but not the other. Try to ensure that any surface that has anything living on it is positioned to face the aquarium’s lights as this will help to encourage growth. This is one of the great things with live rock, you’ll have a fantastic eco system with all sorts of creatures in no time at all.

With your aquascaping in place, this is also the time to add in any additional circulating pumps you may want. The Juwel Vision 180 Marine Aquarium already has a quiet yet powerful Eccoflow 600 circulation pump installed, but many fishkeepers prefer to add some additional power. If you fall into this category try adding an AI Nero 5 Wireless Submersible Wave Pump as this will provide fantastic circulation within the aquarium, minimising the likelihood of dead spots while also keeping fish entertained.

Step 6: Nearly there

At this point in the marine tank setup process, you should have the aquarium largely ready to go with the water matures, live rock in place and the circulation pumps generating plenty of current. From here, there’s only a few things left before you’re ready to add your new marine friends, including turning on the protein skimmer.

Protein skimmers are undoubtedly a great invention and no marine tank should be without one. Efficient models should remove 90% of the organic waste from a marine aquarium, helping to manage the waste produced by any livestock as well as removing any pollutants associated with the introduction of the live rock. Even this miraculous invention shouldn’t be used as an alternative to proper maintenance, and you should continue to monitor your ammonia and nitrite levels. After a week, if you’ve had no increases, it’s time to think about introducing livestock.

It’s also time to switch on the lights if you haven’t already. Ideally, your lighting should be switched on for 8 to 10 hours per day and, just as importantly, it needs to be switched on for the same 8 to 10 hours each day. With this in mind, we recommend you use an electric timer to switch the lights on and off at the same time each day. You can also set this so that the aquarium’s lights are switched on while you’re around to view it, such as in the evening after work or during the day if you work from home.

Step 7: Adding livestock

If you’ve kept tropical fish in the past, you will already be accustomed to the acclimatisation process associated with introducing livestock to a new aquarium and, with marine fish and inverts, there’s only one added element to take into consideration: the salinity.

When introducing livestock into your new marine aquarium, including coral, shrimps and fish, we recommend the following process:

Switch off the aquarium lights
Gently transfer the livestock and the water from the transportation bag into a container (sandwich boxes are great) which can then float in the fish tank
Leave the box floating whilst the water within the container adjusts to that of the fish tank, you can use a thermometer to check
Start to introduce new water from the fish tank, in small quantities, into the container – allowing your tank’s water to mix with the transportation water. If the container has too much water, remove some, but NOT by pouring it into your fish tank
Continue to change the water slowly in the container, until it matches the salinity of the aquarium
Gently release your new livestock into its home.

This process may take several hours, patience is however well rewarded. It’s especially important that you do not expose your livestock to sudden changes in salinity, particularly inverts such as shrimps and corals, as these are very sensitive to these changes.

Note: In step 4 we mention that you should never pour the water from the transportation bag into your aquarium, and there's a very good reason for this. If you’re adding a new marine fish that has been housed in a fish only system at the aquatic retailer, you can’t be sure that they haven’t added any medications into the system that are copper based. Copper is toxic to all inverts. As such the last thing you ever want to do is mix water from an aquarium shop’s marine system that may be medicated into your invert tank! It’s always best to err on the side of caution so don’t add any water from your local fish shop’s system, stick to your own.

Find everything you need at Aquacadabra

At Aquacadabra, we have everything you need to set up a brand new marine fish tank and, with friendly experts on hand to provide guidance and advice, you can confidently approach your new hobby without fear. To get started, browse through the products linked in the marine tank equipment list at the beginning of this guide or, if you’re looking for a space-defining aquarium or more manageable micro-tank, take a look through our collection of state-of-the-art aquariums to find an alternative to the Juwel Vision 180.

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How to Set Up a Marine Tank

Marine fish tank equipment list