Guess me and every other reefer around theses parts got it wrong and we are all just crazy absurb for running ro in lower mainland. My goal when making new water is to start from zero I want the best water possible for my livestock.

IMO yes. No different than saying all us folks around here are crazy absurb for only using one RO membrane, we should be using two or more inline to achieve the same results as you folks down there.

My tap water tests at 14 TDS and I still use an RODI unit, for a measly $130 or whatever it was I want to eliminate as many potential issues as possible. The filters and DI last forever... lol.

I feel safer using it. What if we get heavy rain that washing gunk up from the reservoir or something like that and all of a sudden out TDS goes up?

For real people think its absurd to want the best for animals collected out of the wild to grace us with their presence. If you are worried about cost and savings maybe you belong in the freshwater hobby where everything is tank raised and wnt know the difference.

TDS, total dissolved solids. While the number is of interest, more importantly it's useful to know what those solids are. In most cases since we are talking about potable water, the solids deemed potentially harmful to our health need to be below a certain threshold. All water suppliers test their output into the system & produce reports that should be available on line to the user. I guess what I'm implying here is that your TDS could be as low as 5, but if that 5 includes copper (not considered harmful to humans), there could be consequences for your salt water livestock long term if you don't take steps to filter it out. Good idea to look up the info on your water source & that should help make a decision as to what level of filtration is appropriate to your situation.

As other folks have mentioned, your water source contaminants may change over the season and/or if the utility is flushing the lines or performing other maintenance. Here in the greater Vernon area there are 2 main sources, Kalamalka Lake & Duteau Creek. The city/regional district occasionally switches my tap water source from Kal Lake to Duteau. A heads up is usually published in the local newspaper. In fact this happened just recently when they were working on extending the intake of the Kal Lake source. I was on the Duteau Creek supply & enjoyed much softer water, 46 TDS as opposed to 180 or higher from Kal Lake. A good percentage of the TDS from Kal Lake is calcium, something many of us dose into our reef tanks. Leaves ugly stains on porcelain appliances (read toilets) in our homes & causes us to use more soap to get stuff clean due to water hardness. This reminds me I should check the latest report to see what's in the Duteau TDS, but since I do use an RO/DI system, I can sort of let that slide. A worthwhile investment in my case.

I live in Coquitlam, and I have been using tap water for the past 4 years, running it only through an old carbon filter.
Have been getting red turf algae and redness on sand.
I definitely do not overfeed.

Just bought a vertex ro/di so i've been slowly introducing ro/di water into my 65 gallon.

We'll see in a couple of months if this will solve the algae problem.

I am shocked how inefficient ro/di's are. Such a waste of water to make purified water!!

I bet I flush more water down my toilet in a day than my rodi "wastes" in a week. Sure you send water down the drain but just picture how much water you drain after you fill the bathtub once or wash a load of laundry.

I collect the RO system waste water. There are many uses for it, including toilet flushing. Win- win. My issue/concern is the quarterly water bill more than any waste.

I just purchased the Vertex Puratek Deluxe RO/DI from J&K Aquatics. Price was good And the less headache the better!