RO water from the store dispenser ?s

Just to clarify on the "RO water dispensers" in my area like at Walmart and the Self service water dispenser. I tested both of these with my TDS meter.
First off the TDS of the water in my area ranges from 180-200.
The Walmart water dispenser has a visible maintenance schedule on the machine of when it was last serviced. I tested this water the day after it was supposedly serviced. The TDS meter read 35. Whether it was serviced on that day or not I am not absolutely sure.
I went back the following week and the TDS was at 40. So my assumption is that it was probably not serviced on the date it said it was.

The Self serve water station was horrible, it did not have a service schedule posted anywhere in the open. The water tested at 130, you might as well just use tapwater and not waste your money.

You still need to be careful when using LFS water as well. The LFS in my area is good about keeping the maintenance on thier water source. Most of them keep TDS below 20.
Although I have heard of some of them being alot higher.

If you have intentions of keeping a reef tank you will be better off buying an RO/DI unit. This way you know your own water source and do not have to rely on the LFS to keep up with RO maintenance. If you just plan on keeping a fowler or fish only the other water sources will be fine.

There are lots of sources online where you can purchase the pre-filters and membranes cheap.
 
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