Reverse Osmosis Unit Help

[hwoarangtag]

Hi, I am thinking of going with RO water for my discuses as my water is pretty hard. (tap water > 8)
I have few question concerning a RO unit.

1. I realized there are 2 kinds of RO unit. One is RO only; the other one is RO/DI. What is difference? Which is better?
2. How does a RO unit work? Does it have to be hanged on the near the aquarium like a protein skimmer? Or is it like a water filter attached to the sink and everything is done outside of the aquarium?
3. I see 50 Gallons per day (GPD) on some RO units. How does it work? Does one have to leave the tap water on all day? If so, it will be such a waste.
4. I see a lot of parts for the RO units. I believe some of them should be replaced once in a while. Which parts should be replaced and at what rate(time or usage wise)
5. I see some RO units stated to be a 3/4/5 stages of filtration. I beleieve the more stages the better. right?
6. Are RO units used for household good for aquarium? I ask this because i heard that household tap water filters are not necessarly the best for aquariums.
7. If so, is this a suitable RO unit for Aquarium? -->Kenmore Ultra Filter 150 Reverse Osmosis Water System
8. Last but not least, how much of the RO water should be put in a 75 gal tank during a 20 % water change.

Many Thanks.

 

[xxBarneyxx]

Will try to answer all your questions below

Q)I realized there are 2 kinds of RO unit. One is RO only; the other one is RO/DI. What is difference? Which is better?
A) Basically the DI section will make the water slightly more pure and because it is before the RO filter in the unit can mean the RO membrain will last longer (as it is not filtering out as many impurities).

An RO/DI unit is great but the DI section is not something you HAVE to have.

Q)How does a RO unit work?
A) You connect it up to a cold water pipe where ever is easiest (best bet is to use a Y adaptor to run it of the same line as your washing machine). You then have two tubes coming off the RO unit. One is the waste water and one is the Pure RO water. You need to have somewhere for the waste water to go (Drain for example) and a container for your RO water.

Q)I see 50 Gallons per day (GPD) on some RO units. How does it work? Does one have to leave the tap water on all day?
A) You fit valves to all three pipes on the RO unit (the input, the waste output and the RO output). When you want to make water you open all the valves up. When you have finished you close them all up. You need to do it this way to keep water within the RO system (the RO membrain will break if it goes dry).

Dont expect to get 50gpd out of it though. The temperature of the water and pressure of the source water effects how well the RO unit works (I get about 23gpd out of my 75gpd unit because my water is REALLY cold and has a very high TDS at source).

Q)I see a lot of parts for the RO units. I believe some of them should be replaced once in a while. Which parts should be replaced and at what rate(time or usage wise)
A)The prefiltering media, DI resin and RO membrain all need to be replaced. off the top of my head I cant remeber how often (6 months is recommended for the RO membrain) but normally you can leave it until the TDS of the RO water starts to go up. If you get an RO unit with a Flush Valve this will increase the life span of the RO membrain.

Q)Are RO units used for household good for aquarium? I ask this because i heard that household tap water filters are not necessarly the best for aquariums.
7. If so, is this a suitable RO unit for Aquarium?
A) Pass. There is debate on this but personally I wouldnt recommend it.

Q)Last but not least, how much of the RO water should be put in a 75 gal tank during a 20 % water change.
A) That depends on the stats of your Tap water, the final RO water and what levels you want in the tank.

DO NOT use pure RO water. You either need to mix it with tap water to bring the KH, GH and PH back up where you want it or use something like "RO Safe" to mix with the RO water (does the same thing). Either way you will need KH, GH, PH test kits and if you already have fish you dont want to do massive water changes right away (you need to gradually change the KH, GH and PH. If you do it quickly it will kill the fish).

Make sure you get a TDS meter to check the TDS of your source water and to check the TDS of your RO water. The RO water should be zero (or close to it) when this starts going up you need to think about replacing your RO membrain.

 

[hwoarangtag]

Nice info. Thanks. One more thing, so basically,
I saw this RO unit on Ebay. As far as i can see it's the cheapest. Do you think it'll work?
http/cgi.ebay.ca/AQUA-SAFE-AQUARIUM-II-R...1QQcmdZViewItem

 

[backtotropical]

Hi,

I think Barney answered all your questions, so i have nothing to add there.

Heres where i got my 6-stage, 150gpd system. I'd highly recommend them.

http/www.ro-man.com

Cheers

BTT

 

[hwoarangtag]

Do you guys know if there's any site with live performance of the usage of a RO unit? or maybe a site with instructions on how to setup? I tried Youtube, nothing there...

 

[hwoarangtag]

Also, does the setup of a RO unit hard? Does it involve breaking water pipes? or can it be directly mounted to a tap water outlet.