water chemistry for top off water

[Sanlynn]

I searched in the forum but couldn't find the information I needed, so I am hoping I can find it here.

I tested the water I produce for top-off from my RO-DI unit (all new cartridges and membrane) and found that the phosphate level was brought down to 0, but chlorine is the same as the tap water at 0.5.

I had thought that chlorine evaporated if water was left standing long enough (this water is more than 24-hours old). but I guess I'm mistaken about this. Though, I should add, my testing kits are somewhat expired - still the phosphate was significantly different using an old kit.

In any case, is the top-off water safe to use? Should I be testing it for anything else?

Thanks,
Sandy Lynn

p.s. should be getting my new AI lights within the next two weeks.:spin3:

 

[alanbates12]

Does your tap water have chloriamines in it or is it treated with chlorine?

 

[Sanlynn]

I don't know how the tap water is treated. Not sure how to find out; I can't figure it by the public information on web pages I was able to access...

Sandy Lynn

 

[alanbates12]

Check with your water department to see it your water is treated with chlorine or chloriamines.

 

[Sanlynn]

OK, I'll try to find out tomorrow. If it is chloriamine, does that mean I should run through activated carbon? Or????

 

[alanbates12]

I not the expert by no means in this department but I know they sale RODI systems just for chloriamine. Just find out which they treat your water with and then go from there. Maybe you have the wrong filter in your system. Is this the first time you have used this RODI unit and is it the first time you've tested it?

 

[NicoleC]

Chlorine can be removed with aeration, chloramine cannot. Your carbon pre-filters should remove both of them completely, otherwise they will destroy your RO membrane. If they are not doing their job, you may want to add an additional pre-membrane stage, or upgrade your carbon filters to a higher quality catalytic carbon filter.

 

[Sanlynn]

I tried several times to get a person at the water department to no avail. Maybe tomorrow after the post-holiday crush...

In the meantime, the fellow who set up my system for me suggested I use the same test kit and see how it was reading from the fish tank. (Thanks, Tony!) Since all the fish have been healthy, the assumption being if the ppm matched, it should be ok.

Well, the test kit showed that the tap water, the RODI water and the fish tank water were all a match (o.5)...not sure if the test kit is too old but, I used the water (the skimmer was beginning to suck air) and so far so good.

I'll still try to get an answer from the water company so I know what I'm dealing with.

Again, thanks for your replies.
Sandy Lynn

 

[Patrick12]

If you are on a municipal water supply, then the chances are very high they are using chloramine.........it lasts longer and they are not worried about the aquarist. You should run your water thru a carbon chamber.....most units have this. I am also curious as to how it is making it thru your RO membrane at the same level as the input to it? In any event, you can use Prime or Amquel to neutralize the chloramines and be OK, but you really should not have to do that.

 

[Patrick12]

I also just noticed that you have an RO DI unit. There is something wrong if the chlorine level is anything but 0. The resin should have pulled it out. Double check your test kit. Get some distilled water from the store and see if it too reads 0.5. If it does, you have a faulty kit.

 

[Tomoko Schum]

I recommend that you get a new test kit or take your water sample to an LFS that is willing to test your water for you instead of wondering how to find out if your water really contains any chlorine or chloramine.

You need to make sure that your RODI unit is not damaged. If your RODI unit is fitted with new filters and membrane, there is no reason why you should get any chlorine in your product water unless your carbon filters are spent or damaged for some reason. Since chlorine attacks and damages your RO membrane, you need to check if your carbon filters are working well.

The main concern of chloramine is the ammonia that is released as chlorine is bound to activated carbon. Ammonia can be removed by DI resin, but DI resin can be exhausted quickly.

 

[Sanlynn]

I reached the water department today and spoke to a person in their plant (customer service couldn't answer and just patched me right in). She informed me that they treat the water with chlorine, not chloramine. From what I read that should simplify things.

Next step, new test kit. Looks like I have to order it online since none of the fish stores here (I looked in all three that deal with sw) carry it, so it will be a while.

Thanks again to those who replied.

Sandy Lynn

 

[alanbates12]

Sandy my wife works in Montgomery this Sat at Baptist South and I'd be more than happy to pick you up a test kit and send it with her Sat. Just let me know what you want.

 

[Sanlynn]

pm sent, thanks.

BTW, we discovered today that the TDS meter read 41 ppm for our tap water and 0 for the RODI. I know it doesn't measure chlorine, but I'm happy about it anyway.

Sandy Lynn

 

[gflat65]

41 out of the tap??? I've got something like 250, less than a mile away... It's a killer on RO/DI media.

 

[Sanlynn]

Gary,
Tony told me you'd be amazed! He said our water was similar to what he gets at home.
Sandy Lynn

 

[KingRicky]

In my experience, if you are getting Chlorine after the RO/DI, you have serious problems with it. Any Chlorine that gets to the RO Membrane will cause it to fail and you would need to replace it.