RO/DI Water?

[dan2x38]

Is it OK to use just RO water not di-ionixed in your reef tank? Why do you need a DI unit too?

Does an RO unit remove chloramine?

Should you have a TDS meter attached? How about a pressure gauge?

Looking for tips on an RO unit do not want to waste my money on things not need. I do not need bells & whistle just to say I have them. We also want to drink the water so I know you really shouldn't drink the DI water.

[new2salt]

RO or RODI
To DI or not to DI is the question?
Dan, I really think it depends on the source water.
RO has limitations on what it can and cannot filter out of the source water.
DI takes care or those items that get by the RO.

Test your water source with all of your fresh and salt water test kits, to see where your starting point is.
Maybe look for a system that you can upgrade from RO to RODI.
Start with RO - test all param's and see if you really need DI.
Get a TDS meter - handheld or in-line, I think it is a must have item.

I'm on a well and started with making RODI water before I filled my first SW tank
Did my homework and hopefully started out on the right foot

Quality salt water mix is truly designed to be used with RODI, as all of the extra essential and trace elements have been designed into the salt mix

Just my $0.02 - hope this helps you decide

[redbelly]

RODI all the way Dan!
TDS out of your RO will be 5-8ppm, TDS out of the DI will be 0.

Technically you need a high quality carbon to remove chloramine or it will burn pin holes in your RO membrane.

The pressure guage is usefull but not always required. If you have insufficient pressure then you get a vey poor rejection rate but unless its crazy low you are still making decent water. If you have an auto topoff block on your RODI then the pressure guage lets you know when the unit is still running so say you are filling a 50g barrel and it is at the top if your auto top off block has failed and the water is continuosly flowing through the unit then the pressure guage will still ready a psi, 50 psi for example. But if the top off block is working properly then once the barrel fills the pressure drops to zero and being able to tell when the barrel is actually full can be tricky sometimes. Basically a pressure guage is very usefull but not absolutely required.

TDS meter, I think these are usefull but not absolutely required. If you have a good unit it will be making good water. I would consider this to be a nice upgrade for down the road. IMO spend the extra cash on a good unit today and look at a TDS meter in a few months. A inline TDS meter though is a great way to check on the condition of your RO membrane and of your DI resin. Please note that a MANY RODI units put the "in" on the TDS meter after the last carbon which is a completely usless measurement...
When you get an RODI unit just borrow a hand held meter to make sure its working properly, and remember that the first 5 gallons of water out of your RO unit every time you use it will have a slightly higher TDS hence why the 50g barrels or rubbermade garbage cans are so popular.

Any RODI unit can be used for drinking water, you just want to take the drinking water from  after the RO/before the DI. You will need a T and 2 ball valve for this (total cost approx $25)

[Rybren]

Just to tag along here and add my $0.02

1.  The City of Ottawa uses Chloramines in their water treatment system
2.  Choramines are made by mixing chlorine and ammonia
3.  Good quality carbon stages (preferably 2 of these stages) will break the chlorine-ammonia bond
4.  By the time the water exits the RO stage, all of the chlorine should be gone from the water;  however, some of the ammonia will still be there
5.  The DI stage will remove the remaining ammonia

[dan2x38]

Great guys thanks for the answers.

So to be save shoud I still dose with Prime?

[Rybren]

Dan,

If you are just running an RO unit and you're on city water, then Prime is a really good idea to neutralise the ammonia.  It won't, however, do anything to help you get rid of the other nasties that the RO missed.