RO/DI water question.

[moneylaw]

Hi,
Still new to the hobby, and have a question. Is the water from "pure water" store the same as RO/DI water? There is a pure water store near my house and they are selling pure water for $0.25 per gallon and I am wondering whether it is the same as RO/DI water. Your help is really appreciated.
Thanks.

 

[miaheatlvr]

Originally Posted by moneylaw
Hi,
Still new to the hobby, and have a question. Is the water from "pure water" store the same as RO/DI water? There is a pure water store near my house and they are selling pure water for $0.25 per gallon and I am wondering whether it is the same as RO/DI water. Your help is really appreciated.
Thanks.
It might be Reverse Osmosis, but definately not Deonized which just polishes the water, but most people do not put uch stock into these machines for they cannot attest for the filter maintenence. Maybe get some and do a water test.

 

[trippkid]

I use something similar, I run it through a DI filter then to make sure it is good.

 

[moneylaw]

Is that mean I shouldn't use the water from pure water store? How important that water be deionized? And Do I need to check with the store whether the water is RO or not? Help please, I am starting my tank very soon and don't want to start on the wrong foot. Thanks.

 

[geridoc]

RODI is a very important part of keeping marine fish successfully. Tap water, no matter how "pure" has low levels of contaminants, usually (except for chlorine) too low to be a problem for your fish. However, after your tank is up and running water will evaporate over time. When this happens, only the water leaves the tank, not the contaminants that were in the water when you made it up into salt water. You would then add more tap water, which means adding a small amount of contaminants again, over and over and over. Eventually, the level of contaminants will get high enough to be toxic, and you have a big problem. In addition, there are substances in tap water that, while not toxic, will create problems for you. Silicates, normally in tap water, will support the growth of diatoms (commonly mistakenly called brown algae). Phosphates in the water will help nuisance algae to grow in our tank. That is why RODI is so important - it has no contaminants, phosphates or silicates. Hence, one source of problems is eliminated. But not to worry, as you will learn, there are plenty of other sources of trouble, so you won't be bored.

 

[dawman]

Originally Posted by moneylaw
Is that mean I shouldn't use the water from pure water store? How important that water be deionized? And Do I need to check with the store whether the water is RO or not? Help please, I am starting my tank very soon and don't want to start on the wrong foot. Thanks.

I just have a RO unit , DI just purifies the water the extra 1% . Many Professional Reef keepers told me you don`t need DI . I never have had any problems with using RO without DI .

 

[moneylaw]

Hi Geridoc,
I appreciate your explanation, and I also have read about danger of tap water on this forum, and I am not planning to use tap water at all. My question was whether the water from "pure water" store is good enough or not. Thanks.
Hi Dawman, Do you know (in general) the water from pure water store is RO water or not? I know I should ask that question at that store, but the store hours are very short (and I work late) and I usually just get it from the machine at the front of the store. Thanks for your inputs.

 

[dawman]

That really depends on the store . Some use RO and some just use a carbon filter and claim to have purified water .

 

[snapperboy]

i would take a sample to a LFS and have them test it. some of those "pure water" companies use copper pipping in their purifiers and heavy metals in the water could devistate your tank.

 

[farslayer]

Distilled water should be avoided as well for the copper reasons. "Pure water" is so ambiguous that no one on here could tell you. You would have to know exactly what they did to purify the water. Our local Wal Mart has drinking water which has been through RO, carbon, and UV sterilization, so it's pretty good. But I bought an RO unit cause I'm lazy

 

[moneylaw]

Originally Posted by snapperboy
i would take a sample to a LFS and have them test it. some of those "pure water" companies use copper pipping in their purifiers and heavy metals in the water could devistate your tank.

Thank you, everyone. I will go to the LFS and have them test the water from that pure water store. So what should I ask them to test? Thanks.

 

[farslayer]

You want them to test dissolved organic content, but more importantly grab the label off of that "pure water" and see what it says they did to it.

 

[moneylaw]

Thanks.

 

[geridoc]

See if they can determine the "total dissolved solids", known as the tds. This value should be zero for RODI water.

 

[cgj]

I recently bought a kent marine RO unit. Filters tap and well water. I have well water. The thing is, i had it hooked up by a very skilled plumber, and it works, but somethings dont add up. It filters water a little too fast. The product describes that it can produce 10 gallons a day. This filter will produce 10 gallons over the course of 10-15 minutes... it also produces only a few pints of waste water to produce the good RO water.
I have tested the water and it comes as
Nitrate: 0
Nitrite: 0
Ammonia: 0
PH: 6.8
Phosphate: <0.25
I guess it works... cant see any problems here.

 

[cgj]

Ah.. ok... now i realize what i need to test for is total dissolved solids. How do I test for that?

 

[oceansidefish]

To test for TDS you can contact a company called National Testing Laboratories. They have a test kit called Watercheck, I don't think you could think of something they can't test for. I use it for my comercial clients to test water from domestic main lines. Not entirely cheap though. There may also be local environmental lab that can do this as well.

 

[dawman]

Originally Posted by CGJ
I recently bought a kent marine RO unit. Filters tap and well water. I have well water. The thing is, i had it hooked up by a very skilled plumber, and it works, but somethings dont add up. It filters water a little too fast. The product describes that it can produce 10 gallons a day. This filter will produce 10 gallons over the course of 10-15 minutes... it also produces only a few pints of waste water to produce the good RO water.
I have tested the water and it comes as
Nitrate: 0
Nitrite: 0
Ammonia: 0
PH: 6.8
Phosphate: <0.25
I guess it works... cant see any problems here.

Your unit will run faster than normal for the break in period . You do not want to use the water during break-in . Also make sure you don`t have the waste line mixed up with the purified line . The waste line will be flowing a lot faster than the purified line . Normally after break-in the waste water runs 3-5 times faster than purified water .

 

[miaheatlvr]

Originally Posted by CGJ
I recently bought a kent marine RO unit. Filters tap and well water. I have well water. The thing is, i had it hooked up by a very skilled plumber, and it works, but somethings dont add up. It filters water a little too fast. The product describes that it can produce 10 gallons a day. This filter will produce 10 gallons over the course of 10-15 minutes... it also produces only a few pints of waste water to produce the good RO water.
I have tested the water and it comes as
Nitrate: 0
Nitrite: 0
Ammonia: 0
PH: 6.8
Phosphate: <0.25
I guess it works... cant see any problems here.
I think you might have the "Good" water and "Bad" water outputs mixed up,, the good ro/di water should be coming out at a even SLOW trickle, anything besides this doesnt sound like normal oporation.

 

[larryndana]

most lfs sell ro or ro/di water, i'd check locally to see if they do. in the long run you will be better off buying a unit of your own. just remember tap water is cheaper to filter then buying already filtered water.