15 Science Facts About Why You Need a Reverse Osmosis System For Your Aquarium
1. Tap water that is safe for you and your family to consume is toxic to your fish, corals, and other aquarium inhabitants
While some sources of tap water are far better than others on the general scale of contamination, you never can be 100% sure your tap water is safe unless you purify it yourself.
2. Most of us don't really know exactly what is in the water
Most folks simply don't track or analyze the contents of their tap water on a regular basis. If you do get a hold of a water analysis report, are you equipped with the knowledge to know whether or not those things are safe? Read on to learn more about the potential risks and contaminants that are common in tap water.
3. Do you know the dKH of your tap water?
Upon testing various sources of tap water surrounding the BRS headquarters in Minneapolis, MN, we found there to be a huge variance in the dKH levels. One source tested as high as 26 dKH when mixed with aquarium salt mix! Anything can be dangerous at certain levels, including carbonates.
4. Ammonia is a very common toxin in tap water and is deadly to your fish, even in minuscule amounts
When disinfecting tap water, municipalities will use chloramines which is a mixture of chlorine and ammonia. Here in the USA, more than 50% of municipal water supplies contain ammonia which is extremely toxic to aquatic animals, even in very small amounts. Ammonia causes gill damage to your fish at only 0.05 ppm!
5. There may be more phosphate in the tap water than you think.
During our own look at tap water sources during a BRStv Investigates series, phosphate levels in tap water varied from .05 ppm to as much as 1.8 ppm. Relative to the ideal phosphate level of 0.01-0.03 ppm in our aquariums, this much phosphate in your source water can quickly cause problems in your tank.
6. Nitrate is also commonly found in tap water
Just like phosphate, nitrate can be found in tap water which will ultimately work against your efforts of attempting to remove nitrates from your aquarium if your source water is not purified first.
7. Every municipal water supply uses some form of disinfectant, usually chlorine or chloramines
Both chlorine and chloramine are used to disinfect tap water and will be toxic to your tank.
8. There are a wide variety of additional contaminants that could be present in your water and only ICP testing can ID them.
In addition to the aforementioned common contaminants, there is a wide variety of heavy metals and various other contaminants that could be present in your tap water and would be unwelcome additions to your aquarium. This may include arsenic, copper, silicate, uranium, lithium, and a swath of others that will vary depending on your exact source. These levels could vary drastically and the tolerances are relatively unknown as it pertains to fish and corals.
9. There are certain contaminants that cannot be monitored via testing
Pesticides, herbicides, and various other chemicals that make their way into the water table may not be monitored or regulated but are still dangerous to your tank.
10. Sediment filters physically remove suspended particles/sediments and helps extend the life of your RO/DI filters
A sediment filter is arguably the most important filter in a reverse osmosis system because it removes dirt and debris that will otherwise fowl downstream filters.
11. Carbon block filters remove chlorine and other chemicals
The second stage of filtration in your RO/DI system is the carbon block filters that manage the removal of dangerous chlorine, ammonia, and other chemicals. The caveat here is carbon filters are not 100% efficient meaning they will not always remove 100% of the chemicals and they become less efficient over time. This is why we typically recommend x2 inline carbon blocks to ensure your doing the best possible job of stripping chemicals that could easily damage the subsequent RO membrane.
12. The RO Membrane is the workhorse of your RO/DI system
An RO membrane does a majority of the work in your RO/DI system in terms of removing those difficult contaminants. It works based on pressure where the water is forced through progressively smaller permeable membranes that gradually filter out various molecules with only the clean water molecules making it through to the end.
13. Deionization or DI resin is the final stage of filtration and ensures nothing sneaks through your RO/DI system
The last and final stage is designed to remove ANY contaminants that MIGHT make their way through the various stages of RO filtration. DI resign works by taking advantage of the electrical charge of ions and filters out both negatively and positively charged ions; a mixed bed DI resin contains both negatively and positively charged ion removal resins. Water exiting the DI filter should measure 0 TDS meaning nothing exists in the water except pure H2O.
Your aquarium water will never be better than the water you start with and the quality of your water is extremely important for the long-term health of your tank. In many cases, tap water will not be immediately toxic meaning you can use it once or twice without any ill-effect in the aquarium. It is the repeated use of tap water over time that will create a build-up of toxins and eventually become a problem.