reverse osmosis question

[newbeemike]

I have a RO system under my sink at home that I bought from rainsoft. Can I use this water to top off my tank. Is there a difference between ro and ro/di? I have not used it and noticed it looked almost identical to my local petstores system that they use to make water I m constanly buying? am I waisting my money using there water when I can use mine?

[RyanG]

The RO water should be A-Ok grab a TDS meter and check it against water that doesnt go through your system. Say from the bathroom sink. Im not versed in Total Dissolved Solids numbers you might have to search and find out what is an acceptable number.

[bri74]

should be ok give it a test though to make sure

[Bifferwine]

Most RO units will bring the TDS of tap water down by around 90%. Adding the DI component brings the TDS of tap water down by around 99%. What is considered "good" TDS is relative to where you're coming from. Here in Tucson, where tap water tests out with a TDS of 400+, getting it down below 50 is considered a success. My RODI unit at home brings my tap water (at 400+) down to below 10, and that sounds great to me. The closer to 0 you can get it, the better.

[fatman]

An under the sink model will work fine except that you will need to drain the storage tank several times a day and store up the water to use as needed (or slip a hose over the filtered water faucet and run it to a large storage container). In most parts of the country calcium levels are only in the 100 to 250 ppm range and you can expect to remove around 95% of all calcium and higher percentages of other solids. For most reefers RO water is sufficient. There are areas like the Southwest where DIO filters are pretty much needed in addition to an RO filter. All producers of water who sell that water as potable water must have the water tested so your regular water supplier will tell you what the residual hardness is as well as what heavy metals are present. If these levels are high then a DIO filter can be readily added to your system for around $50 retail (parts wise). Expect about 20 to 25 gallons a day (per 24 hours) of water from a typical under the counter model with small tank and faucet. Here in Fairbanks, Alaska the use lime softening to lower the calcium level down, by overloading the water with calcium and thereby causing precipitation of calcium. It gets the calcium hardness down to around 125 ppm but the total dissolved solids is still 350 to 375 ppm. The RO I use gets it down to around 10 and the DIO gets it down to a zero reading of total dissolved solids.

[newbeemike]

Were do I get a TDS tester. is that something sold at a petstore?

Originally Posted by Bifferwine

Most RO units will bring the TDS of tap water down by around 90%. Adding the DI component brings the TDS of tap water down by around 99%. What is considered "good" TDS is relative to where you're coming from. Here in Tucson, where tap water tests out with a TDS of 400+, getting it down below 50 is considered a success. My RODI unit at home brings my tap water (at 400+) down to below 10, and that sounds great to me. The closer to 0 you can get it, the better.

[Piggy]

I got mine off ebay.

[RyanG]

Foster and smith or marine depot will have them. Maybe your LFS will be able to order one for you or you could check at a water store like culligan etc.

[fatman]

http://www.waterfiltersonline.com
http://www.airwaterice.com/product/S...ter_Senno.html
There are hand held models that run $25 to $35, and dual models that are installed so that they constantly monitor the TDS of both the in coming and out going water. A hand held model is sufficient but a dual is more convenient. The dual takes only a minute or two to install. Every thing is slip fittings, no wrenches needed.

[Bifferwine]

I got one off of Ebay for $25. It has a digital thermometer built in too.