Thinking of investing in a RO

[catfishchaos]

I'm in Nova Scotia, Canada and After testing my Ph a few times for my tap water I'm finding consistently a 7.5 average which I know is ok for the fish I have (Tetras, Clown plecos and the L134 I'm picking up tomorrow ) But I would like to bring it down a notch (Ideally 6.5-7.0) Would an RO be a worthy investment?

My following questions are pretty basic.

What model would you recommend? I do weekly water changes for my 55 gallon (usually 30-50 percent or 2.5-3 10 gallon buckets. Is there a RO system that could go directly from system to bucket (with a hose) as connecting it to my tap water would make filling said buckets very difficult.

What are the price ranges? I really don't want to go over $200.

What unit size would be minimal? I really not looking for a heavy duty or industrial model as I only one take and limited space.

Thanks for your time
Regards
James

[lilu]

I use an RO unit because in the part of Montreal where I live the quality of the water is very inconsistent. It happened to me twice where after a regular water change 1/3 of my fish died overnight (I used the same dechlorinator as usual and tried to match the temp)and then came bouts of illness - full recovery of the tank took a couple months. What had happened is the city was doing work on the water pipes a couple blocks away and I hadn't realized the effect that could have on the water.

I started off with a 75GPD basic Spectrapure unit (only a sediment filter, a carbon block and one membrane). The TDS entering the unit is ~145-160, after the unit it is 2-4. It is plumbed in directly under the kitchen sink to the incoming cold water supply. The waste water is plumbed into the drain under the sink. The product water fills a 12G holding container in the next room (had to cut a hole in the wall to send the tubing through) from which I do auto water changes. To reconstitute the water automatically I use a dosing pump to add the liquid version of seachem's KH and GH supplements. For example if a water change happens at 4pm, the dosing pump adds the correct amount of Mineralize (GH) and Carbonate (KH) for the amount of water that was used in the water change process to the KH/GH I want, it also adds some trace minerals (Fish Trace).

Recently we had a decrease in water pressure (again coincident with ongoing construction across the street that never seems to end ) I added a 150GPD water saver upgrade to the RO unit. This way the 'waste' water from the first membrane goes through the second membrane and more water is produced (with a slightly higher overall TDS ~6ppm) but there is less waste - but because the pressure was low (~58PSI in the water from the incoming water line) I added a booster pump (min PSI for the 150GPD units should be 65PSI). The pump raised the pressure to 80PSI so now it takes no time to fill the 12G container (float valve and auto-shutoff valve turn of the RO unit and the booster pump off when the container is filled). With this set up I put a T connection with a ball valve at the end in the product water line so I can fill any other container independent of the holding container at any time.

There are simpler ways to reconstitute RO water using powdered products - I used to use Equilibrium (from Seachem) plus Acid Buffer and Alkaline buffer in a 1:2 ratio but in the end I found the liquid products to be more suited for what I needed.

This is a Canadian supplier with one of the best prices I've found online - the basic unit is $165:
http://www.reefsupplies.ca/online-store ... e-Osmosis/
You would also want an auto shutoff valve ($32) http://www.reefsupplies.ca/online-store ... apure.html so that the unit stops producing waste water when you manually or automatically stop making the water.
While not necessary, but useful, an inline TDS meter will tell you the quality of the water entering and exiting your unit so you know when it is time to change the membrane: http://www.reefsupplies.ca/online-store ... meter.html ($35)

Unless you have very poor water it is unlikely that you would need a DI canister so that saves a considerable amount both upfront and over time in replacement resin.

[David R]

If all you're testing is the pH, you should spend some money on GH and KH test kits and a TDS/conductivity meter before even thinking about buying an RO unit.

As lilu mentioned, there are different reasons for wanting/needing RO; is your tap water poor/inconsistent quality, or simply too hard for the fish you wish to keep? This will probably determine whether you use straight RO water [remineralised, of course] or if you can cut your RO water with tap water to achieve the desired hardness/mineral content.

IMO, unless your hardness is through the roof an RO unit isn't going to be necessary for you if you're just keeping a community type tank. Also, depending on what the atmosphere around you is like, catching rainwater may also be a cheaper and easier source of soft water.

[catfishchaos]

Holy Informative, thanks guys!

David I think I'll grab some of those test next time at work and check it out.

Strangle enough my tap water tested (PH) out at 6.5 and instantly after putting it into the tank (water change) it instantly read back at 7.0-7.5, I knew seachems onyx sand raised the PH a bit but had no idea it had such a big/instant effect!

[David R]

That is probably an indication of very soft water then. The hardness is what provides a buffer to keep your pH stable, water with little hardness (or none at all, like RO water) will fluctuate up or down very easily, which is why it is important to either remineralise your RO water or mix it with hard tap water to provide enough hardness to keep your pH relatively stable.

If your tap water fluctuates like that, and all you're trying to achieve is a slightly lower pH, then an RO unit will almost certainly be a waste of money. Look at the decor in your tank and figure out what is keeping the pH up above 7 and remove some of it. Soft water + fish and wood will usually see the pH dropping steadily, unless there is something else providing a buffer. Anyway, post the results of your GH, KH and TRS/conductivity for the tap and tank water and all will be revealed!

[Narwhal72]

Keep in mind that the timing of when the tapwater was tested is critical. Oxygen will become depleted in plumbing and excessive CO2 will drive the pH down. It is quite normal for tap water to be at a lower pH coming straight out of the tap.

Aerate the tap water with an airstone for a couple of hours or let it sit for about 6 hours stirring occasionally and test again. This will tell you what the true pH is of your tap water.

But like others have said, the true determination of whether you need an RO is not pH but GH or TDS. A simple GH test kit can tell you whether you have hard or soft water and how the RO will benefit you.

Andy

[apistomaster]

If all you are doing is trying to maintain the one aquarium I doubt you need to spend money on any RO unit. There must be 10's of thousands of successful casual aquarium hobbyists in the Metro Montreal area who use only tap water without incidents.
In any case, it has been good advice for you to first acquire the water tests and/or meters to be able to get a more complete understanding of your tap water. That is the most important first step.
If you do find a need for an RO unit you should check out http://www.airwaterice.com.
They offer a variety of complete sets of varying daily capacity at very good prices.
Many of their kits include an automatic shut off valve and a float switch.