RO/DI units

[zoo-a-holic]

With all this talk of RO/DI units, it makes me wonder, what are some of the advantages and disadvantages to them???

[Guido]

Well, i don't own one, but from what I've read and reasearched on them, the main advantage is much healtier water for your corals. Most RO/DI units will remove at least 95% of all impurites (iron, chlorine, or w/e else that the water plants put into your tap to make it safe for you to drink (what doesn't harm us, doesn't mean its not going to harm something else like your corals)). Disadvantage i would think would be more money spent, maybe a little maintenance, and buying new cartridges,resin, or w/e it would need to operate at 100%. I personally am buying one before i set up my tank... i wouldn't feel like running back and forth from the store just to fill, top off, or do a water change in my tank, plus it saves you money in the long run. Just my input, someone else with one will say something soon I'm sure.

[dakar]

Having your own RO/DI is for the most part far more cost effective than buying water from a grocery store (generally just RO) or from an LFS. It really depends on your tap water and how it is treated as to how effective it is going to be for your situtation. On the other side even the cleanest water can contain some serious amount of nitrates (we all hate these), phosphates (promote algae growth and other issues). Is your house plumbed with copper pipes in your house? Guess what deadly element you are introducing to your tank....

Even for us with relatively clean well water, I'm able to measure Phosphates at 2-3ppm, and a Total Disolved Solid (TDS) count of around 387ppm, what those disolved solvants are I have no real clue, it was cheaper to spend $100 on a good filter and TDS meter and not have to worry about them than it was to send in a water sample to have it analyzed.

The cost of maintenace has been minimal, after 18 months and over 3000 gallons of water made my maintenance cost has been $18 (for enough DI resin for 3 refills, so far only replaced it once). Maybe next fall I'll replace the carbon elements and RO membrane if needed (they run about $50 for all of them in a replacement package).

Then again some folks have been able to get away with using nothing but water straight from the tap without issues... but this is generally a select few exceptions and not the rule.

[jerryc]

RODI is for most the #1 item for keeping a good healthier reef i have around
260tds from my water and with the RODI it is 0.0 with it your fish and coral will be much happier
And as daker said the Maintenance is not that bad after a year i just spent
$21.00 including shipping for DI resin the first i have spent on it

[zoo-a-holic]

do you know how much they cost to start out with??

[shovelhead91701]

I think most of us went with the filterdirect unit off Ebay and mine was the top of the line w/ pressure tank etc. about $125.00 if I remember correctly.

[zoo-a-holic]

thats it??? wow, i thaught it would be worse than that. how big is this unit???

[shovelhead91701]

The filter unit needs to be mounted on a wall etc. It is about 2' x 2' and the pressure tank has a footprint of about 15"x15" about 2' tall. See:http://cgi.ebay.com/USA-110GPD-RO-DI-REVERSE-OSMOSIS-water-purification_W0QQitemZ7717460288QQcategoryZ20756QQ tcZphotoQQcmdZViewItem

[dakar]

The pressure tank is optional, used for drinking water and such. Though I opted out for it on mine, I'm sorry I did, should have spent the extra few bucks even if I didn't need it, now I'd like it.

Easy solution though, I'll just order another complete set up, that'll give me a new set of filters for when I need them, the pressure tank and stuff so I can add a drinking water tap upstairs.... and I'll have the rest of the unit to modify into a two stage calcium reactor and a kalk reactor.

[zoo-a-holic]

i have been seriously considering getting one, but do not have an ebay account... ora credit card!!! (my parents dont feel comfortable with theirs on the net)