Most marine aquarists use artificial seawater for their aquaria. This is usually made by combining a commercial mixture of appropriate salts with suitably pure freshwater.  When it comes to choosing a sea salt mix to buy for making up synthetic salt aquarium or reef tank system water, you want one that is as close in composition to that of natural sea water as possible, as well as has no or little other unwanted impurities contained in it, like phosphates. S eawater is approximately 96.5% water and 3.5% salt, by weight.  When the salinity of seawater is referred to as being 35 ppt (parts per thousand), that is the same as saying 3.5% salt.  Seawater is composed of many different ions (salts), with the total of all adding up to the 3.5%.  Some ions are present at very high concentration and some at very low concentration.  However, even those present at very low concentration can be important to organisms living in the water. The main ions in seawater, in order of percent by weight, are chloride, sodium, sulfate and magnesium. You may ask what salt mix is best? Many aquarists just use the cheapest one that their local stores have in stock.  To be honest, the evidence for using one salt mix over another is marginal at best.  Certainly some are better though then others, and some may be downright undesirable, but no simple ranking can be made. I n addition to using a suitable salt mix, it is important to use suitably pure freshwater, both for making salt mixes and for topping-off for evaporative losses.  The majority of experienced and successful reef aquarists in the U.S. appear to use RO/DI (reverse osmosis/deionization) to purify tap water.  A properly functioning RO/DI filter is always adequate to purify tap water that is otherwise drinkable. Many brands of these filters are available, we at www.oceanreeflections.com have many brands styles of  RO/DI Filters http://oceanreeflections.com/ro.aspx   available. Try to avoid Tap-Water in your reef tank,  the use of tap water itself entails a number of concerns besides the presence of chlorine.  First is chloramine, which does not dissipate after sitting around, the way many aquarists have done in the past for chlorine.  It is now being added to many water supplies, and is much longer lived than chlorine.  It also requires special treatments, not just the standard dechlorinating agents.  Other concerns with tap water are copper (which often comes from your home's plumbing), nutrients (nitrate and phosphate) and alkalinity (which is not  a huge problem, but can boost levels too high in some cases). Measuring your salinity regularly is one of the most important aspects of reef keeping! What salinity is best? Keeping it as close too (nsw) natural sea water as possible is best! If the organisms in the aquarium are from brackish environments with lower salinity, or from the Red Sea with higher salinity, selecting something other than 35 ppt may make good sense. Otherwise, we targeting a salinity of (nsw) 35 ppt (specific gravity = 1.0264; conductivity = 53 mS/cm).

Fortunately, coral reef aquaria seem pretty forgiving different salinity.  The range of salinities encountered in what most successful aquarists consider successful reef aquaria is actually quite large.  Don't stress and agonize over small deviations from natural seawater.  You will not notice any benefit changing from 36 or 34 ppt to 35 ppt (specific gravity = 1.0256 to 1.0271).  Many successful aquarists appear to run at salinity levels as low as 31 ppt (specific gravity = 1.023), The best advice is too keep your salinity between 1.023 -1.026.

There are a variety of different ways to measure salinity, including refractometers, hydrometers and conductivity probes. These devices report values for specific gravity. All of these devices can be suitably accurate, and all can be also inaccurate, mostly when not used or calibrated appropriately. Temperature has little effect on seawater's salinity or specific gravity, but can impact and cause errors in the measurements themselves.  Effects on the measurements are not generally a big problem, except for floating glass hydrometers and refractometers that do not automatically compensate for temperature (most do). We at www.oceanreeflections.com sell many kinds of refractometers to measure your salinity.

Mixing your salt water- F irst, add the freshwater to the mixing container.  The container can be any size, just make sure the container is not made of any material that will leach unwanted chemicals in your water. Do not add anything other than salt mix to the freshwater unless you determine, after mixing in the salt, that it is deficient in something important.  Add the salt and stir.

Stirring with a  powerhead  is a good way to dissolve the salt, but shorter stirring can be okay, if done vigorously.  If you are using the saltwater for very small water changes (2% or less at once), you need not heat it.  Many aquarists like overnight stirring with a pump to help with better aeration of the salt water.   We at www.oceanreeflections.com sometimes do not aerate our salt overnight we will mix it and measure it,  let it sit a 1/2 hour too an hour then measure salinity and temp one last time make changes if needed and then add the display, we have never seen any problems from adding mixed salt water too the display shortly after mixing, as long as you make sure though your salt mix is "VERY'" well mixed,  correct salinity and correct temperature before adding!

Things to remember when mixing salt-water:

1.  Don't focus on "perfect" salt mixes (BRANDS), they don't exist!

2.  Natural seawater might be a fine choice for a coral reef aquarium.  If using natural seawater, be sure it is collected, treated and stored in a suitable manner.

3.  Don't get all worked up by every salt mix comparison that comes along.  A variety of brands of salt mix have been used successfully - Reef Crystals, Instant Ocean and our favorite Tropic Marin (Pro Reef and regular) Red Sea and others.  If you select one of these quality salts, it is unlikely that any failures you will encounter will relate to a problem with the salt mix.

4.  Try and always use RO/DI Freshwater to make the salt mix and top-off for evaporation.

5.  Use an accurate refractometer , and check your salinity regularly.

Formula:  Formulas for Using Salt To calculate gallons in a rectangular tank, multiply length X width X height (in inches) and divide by 231. To calculate gallons in a hexegon or other multi-sided tank with equal sides, measure the total perimeter and multiply by the width of a single side. Then divide by two and multiply by the height (in inches) and divide by 231. One cubic foot of saltwater weighs 64 pounds and contains 7.5 gallons. One gallon of saltwater weighs 8.5 pounds and is 231 cubic inches in volume. Full strength saltwater contains 35 parts per thousand salt and has a specific gravity of 1.026. Approximately 2.9 pounds of salt mix is required to make ten gallons of full strength saltwater. 3 cups of salt mixed in 5 gallons fresh water comes to approximately a 1.026 salinity.

Here at www.oceanreeflections.com we carry many brands of Quality Salt Mixes that would all work great for any salt water reef and marine environment list below are our salt brands that we carry, If you have any questions we can be reached at service@oceanreeflections.com

QUALITY MARINE AND REEF SALT

Tropic Marin 

Red Sea 

Instant Ocean 

Oceanic