Your filtration needs are completely dependent on your water source, many people using RO don't need to as their water source is good, others do. Here in Saskatoon I get a TDS around 200 from the tap, I require an RO membrane to get a reading in a range I consider acceptable. Many other places, especially in BC, get readings in this range right out of the tap. In addition TDS can be misleading, it gives no indication of what the solids are and since some are worse than others it's hard to say what is safe and what is not.

It's a tricky subject, some will swear by one method and others by another. But it really depends on your water source which can even vary greatly within the same city.

I would personally say that if you can get a TDS reading of 25 or less without RO you really don't need it, but that's just my personal opinion. I do however believe you should use some kind of sediment filter and a carbon block at the very least to remove the chlorine and other chemicals, I think is would be much better than using additives.

Here in Kamloops they have RO out of the tap it is also UV sterilized I also use a comersial filter system as it take out any impurities porcilin carbon filter I can obly get replacments filter cartiges from the manufaturer. They use these filter in places like oOrange Julious and Tim Hortons to name a couple. It will take the alcohol out of alcohol to leave you with pure water. The water in my tank has got to be pritty good. just don't leave your lights on a reverse cycle 16 hours a day for more than 1 day algea blooms I can tell you first hand. I made a mistake programming a new timer. I am going to have to get one of those power bars that have a timer on it.

Bill

by looking at the poll i thing its time ro get a ro/di unit now its just a matter of what one lol ?

Been using RO-DI since April this year and in my case, a very good move. So that's almost two years of using treated tap to just over six months of RO-DI. My tank and live rock came from pre-owned systems and I'm still dealing with hair algae but have noted a marked improvement since switching to RO-DI. I have no idea of the true history of my LR so I suspect part of my algae issue may be coming out of the rock. Pretty sure neither of the tanks the LR came from had been using RO-DI, so it could be a while until the algae issue is resolved. I don't sweat it too much since I figure the algae is taking care of whatever stuff is coming out of the rock and in the big scheme of things, the algae is not really harming any of my inhabitants at this point. I do my best with manual removal during water changes.

I did a bit of research while using treated tap, such as checking the stats on my water source, which comes from Kalamalka Lake here in Vernon. Greater Vernon Services provides a water quality chart based on sampling at the pumping station, but I'm not too sure what if any further treatment is applied downstream of that. The chart is updated periodically, haven't checked in a while since I'm now using RO-DI. Some of the values were actually beneficial such as trace levels of calcium and magnesium. Alkalinity was quite high and pH was in the ballpark at 7.8. TDS was listed at 238 and I've been testing it at around 210 from my tap.

Anyhow, what I'm trying to bring to the table here is that anyone using tap water will be well served to investigate their source & get some numbers in order to make an informed decision as to whether RO or RO-DI may be of benefit to their system. Why would I use a RO-DI system and strip all that good calcium and magnesium from my nice lake water? Because there's all kinds of other stuff in there that is not so beneficial and there's currently no alternative to selectively remove the bad stuff and leave the good. The rubbermaid tub I used for mixing up water while using tap water has quite a build up of whitish powder/scale etc. No doubt quite a bit of that ended up dissolved and in my tank, for better or worse. Since switching to RO-DI I also started using a new container and there has been no build up on it whatsoever.

An added benefit to RO-DI is that I can make up RO and have very pure water for my coffee, car radiator, steam iron..... I'm even thinking of getting a small CO2 system, not for my tank, but to make my own soda and give Coca Cola a run for their money. Save a lot of money on bottled water and soda pop that way. So while on the one hand there's a lot of waste water produced by RO (which can be used in other constructive ways), on the other hand you're benefiting the environment by not buying all that bottled water that has to be transported all over the place and then deal with the garbage/recycling of empties.

Ro/di

Here in regina i have a TDS reading out of the tap at 350ppm.

Red Coral in Calgary has a 75GPD RO/DI unit that they sell for $199.

i use RO/DI from the store but top off with water through a brita fiilter

lake water
 

I live on okanagan lake and the house runs on lake water so I just have a float in my sump and I think the sps like it

I'm not sure what the TDS is here in Edmonton but I've used RO water ever since I started my tank and recently upgraded to RO/DI unit. Got one with a booster pump and flooded my kitchen 5 times now.:lol: