Hi, I was wondering if it is necessary to use RO or DI water instead of unchlorinated tap water.
IME, yes RO/DI is necessary for saltwater tanks especially if you want to keep corals. You will be dealing with excess nutrients getting in your tank if using tap water that will lead to algae problems.
I also ran into a strange problem that i can only attribute to build up of heavy metals... I lost a different animal from each tank ( a fish in one, a shrimp in another, and a clam in another), but when I switched to RO/DI no other unexplained losses occurred.
For salt water tanks yeah it can be. Salt water tanks need to stay very stable water wise, and RO is the best way to do that.
Yes, will prevent a lot of headaches down the road with algae blooms, etc.
RO also removes a lot of excess badness, including but not limited to - pharmaceuticals (drugs like asprin and heart medication - only has a binding rate of 50% - which means the half is excreted and in your water!), heavy metals, etc.
And like the others mentioned, it also prevents algae bloom.
yes to add to Kam's point it doesnt neutralize hamfull chemicals like Seachem Prime would or similar. It removes them from the water completely making 100% pure water as long as the unit is functioning correctly.
RODI is necessary, you can make your own or buy it at the store
One way to look at it is... Why wouldn't you use RODI? Down the line you would have invested hundreds and thousands of dollars into a reef tank.
The last thing you want to skimp on is the water source. RODI is suppose to remove all the impurities within your water source to achieve 0 total dissolved solids. If you are using RO, you can get away with it, but there are no guarantee as to what's the remaining TDS within RO water, so lets say there was a low % of copper in the RO, over time the amount of copper will accumulate and become harmful to a reef tank.
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