Adding Water To Your All In One Aquarium


You are so close to having your system up and running.  Step 1, choose the perfect Reef Casa tank for your needs and set it up in an ideal location.  Check.  Step 2, carefully plan your aquascape using dry rock. Check. Step 3, add live sand if desired. Check.  Now it’s time to add water to the tank and start to bring it to life.


How to measure and mix salt will be covered in the next article but for now let’s talk about different options for the fresh water that you will mix the salt into.  The quality of water that is used in an aquarium is probably the single most important factor in helping to avoid nuisance algae, diatoms and other issues in a reef tank.  Other than buying premixed salt water from your local fish store (which can become quite expensive) there are three main options, in order of complexity and cost, for how to produce fresh water for mixing.  These are; tap water with water conditioner, reverse osmosis (RO) water and reverse osmosis de-ionized (RODI) water.


By far the cheapest and simplest method is to use tap water with a water conditioner.  Reef Casa sells and recommends SeaChem Prime for this. It has been used for over 2 decades to remove elements such as chlorine and chloramine and can detoxify any ammonia or nitrites in the source water.  While this method is inexpensive and quick, it will not remove all the impurities from tap water.  Long term tap water use can contribute to issues with nuisance algae as well as other contaminants.


The next option is to use reverse osmosis, or RO, water.  Reverse osmosis water generally uses a three stage system and will provide water that is completely free from chlorine and other chemicals as well as being pH neutral and containing no water hardness.  RO Water can be purchased at almost all supermarkets and drug stores or can be made with RO water filters. This will ensure that your water is safe for fish and invertebrates.  This method also does not remove elements such as silica from the water.


The gold standard for water quality is reverse osmosis de-ionized (RODI) water.  This setup adds a fourth stage where the water is passed through a de-ionization cartridge that removes any remaining elements.  You can test your water with a total dissolved solids (TDS) meter and it should read zero when using RODI water.  This essentially means that you are using pure water with zero contaminants.  Of course, adding a fourth stage means a slightly higher cost, since you will need to purchase a new de-ionization cartridge when the old one is exhausted.  Thankfully, most cartridges change colour from blue to brown as they are used so you will have a pretty good idea when yours needs changed.  A TDS meter can also help confirm that.  Another downside is that this method can be somewhat slow.  A 5 gallon bucket will take about 2 hours to fill, meaning that you have to plan ahead.


As with many things in this wonderful hobby there isn’t really a correct answer for the question “what type of water should I use”.  It really comes down to what your goals and priorities are.  For a fish only tank reverse osmosis or tap water with a water conditioner will be sufficient, but for a thriving reef tank it might be a good idea to use reverse osmosis de-ionized water to help avoid nuisance algae and for optimum coral health.  If you have any questions about what water system is best for your needs please reach out to us at Reef Casa and we will be happy to help!  Happy reefing!