The importance of good source water
A good source of water is an essential base for your home reef aquarium, all the life inside your tank depends on it. In the past, it was acceptable to use tap water in your reef aquarium, but time and analysis has shown that tap water can vary from place to place and may contain unwanted elements for our tanks.
Measurement of water is often done as TDS or Total Dissolved Solids and gives us a guide as to how many impurities are in our water, but we don’t always know what these dissolved solids are.
For example here at Kraken our tap water is a very respectable 28 TDS, that’s really low, some areas can reach as high as 450 TDS from the tap, but we know from testing even at our 28 TDS that the issues with the water are Silicates, Nitrates and Phosphates, three main ingredients we don’t want.
Know your water source.
Good RO Water can be purchased from your local fish store, but this isn’t always the most convenient. You can buy a home RO filter which can be more cost effective, especially if you have a larger tank.
We recommend a 4 stage RO filter which makes your water RODI (Reverse Osmosis Deionized), you can use RO only but the DI resin stage will help remove the final impurities from your water. You do not want a unit that remineralizes the water, this is good for drinking water, but not for your aquarium.
The Four Stage RO Unit.
A four stage RODI Unit comprises of the following;
Stage 1.
A pre-filter, usually white (although not for long) this pre-filter is a basic sediment filter like you might find in a drinking water filter.
Stage 2.
Carbon filter, this is usually a black cartridge filter and is used to remove unwanted impurities from the water.
Stage 3.
The Membrane. This is the filter that’s doing the big push on water. It can remove up to around 98% of impurities and metals etc. to do so however it rejects water, the bad water goes down the drain (or can be used for watering flowerbeds etc.) as waste, and the good water comes out hopefully with a much lower TDS than went in.
Stage 4.
DI Resin, as a final stage the good water from the membrane is passed through a final DI resin filter and at this point your water should come out at around 0-1 TDS.
The speed at which an RO machine filters water can vary massively. Different size membranes can process different amounts of water but equally, if not more importantly, the pressure of the water makes a difference to the amount of water produced and the amount of rejected water. Also, in the winter when temperatures are lower, water production speed is generally lower.
Water Storage.
Storing your water, be it Salted RO or plain RO is important, whether you get the water from your local fish store or make it yourself, ensure your water containers are clean and the correct grade.
Tubs made for drinking water are ideal, this is a high grade plastic that doesn’t leach. Make sure yours are clean and haven’t been used for other chemicals. There have been cases where barrels previously used for other chemicals have been rinsed but some remnants remain in the barrel and this can cause the loss of livestock in your aquarium
All in all its important to have a good quality source water before adding your salt or for your evaporation top up requirements whether you make it yourself at home or purchase it locally from a store.