ammonia in my RO water

[snakeblitz33]

Yep, that's right. There is .5 ppm ammonia in my top off water that is coming through the filter. So, every single time I top off my tank I am adding ammonia and possibly nitrate and phosphate as well since my DI resin is exhausted.

No wonder stuff slowly starts to die in my tank. I'm adding ammonia on a daily basis and possibly chloramines on top of that. Doing some research, chloramines need additional time through a highly dense carbon based media so that it can completely rid of it before it enters the membrane. I guess the best plan of action is to add an additional double carbon filter and have a third carbon filter on the main unit. What can you do for ammonia though? Shouldn't the DI catch ammonia?

I just read that in the area that I live in, they use monochloramine in the water supply, which is basically chlorine gas mixed with ammonia... I'm guessing that the chlorine part of the compound is removed and the ammonia is still going through the membrane and not being removed... Will carbon uptake ammonia, or am I looking at getting a different type of filter?

Basically, I don't want to just replace my filters and end up basically putting a band aid on the situation. I want to fix it and keep it fixed, since top off water and water quality is perhaps the first priority in keeping SPS corals thriving.

Usually I know most of the answers, but it really IS true - we all still learn this hobby every single day.

 

[snakeblitz33]

Tds readings...

This is my TDS reading as it comes straight from the tap... 500ppm


This is my TDS reading after it goes through three filters, an RO Membrane and a DI resin... 40ppm



Now it makes sense why my 75g was so affected. No wonder that nepthia shrank up on me so much and other corals were pissed off... I just have to get my water quality right and everything should be peachy again.

So, what is the best course of action at this point?

 

[bang guy]

I need more information. How often to you replace the carbon filter and how old is the RO membrane?

The DI is shot, no getting around that but even just an RO by itself should do better than 40.

 

[snakeblitz33]

I replace all the filters every six months or as needed. It's the six month mark and I checked the TDS a few weeks ago and it was at 27ppm... and has risen by 13ppm in three weeks. The carbon filter is a GEM coconut filter, actually, which is sold by airwaterice. On the selling points of this filter, it says it is perfect for removing chlorine from the water before it enters the RO membrane, but it makes no mention of removing chloramines. I found a different filter, called a catalytic carbon filter, which they proudly state removes both chlorine and chloramines from the water. I'm thinking that it's possible that the chlorine/chloramine degraded the RO membrane, and that is why it's 40ppm instead of 5-10ppm like it should be with just the RO membrane running. I'll probably have to replace the RO membrane as well or else the next DI cartridge I have will exhaust too rapidly.

Just trying to make sure this doesn't happen again.

Do you think I should add a couple of additional filter housings and add a couple of these catalytic carbon blocks as pre-filters or do you think that replacing the GEM coconut filter with one of these catalytic carbon filters should be enough?

 

[btldreef]

WOW!
Bang Guy is right, even a cheap RO unit usually lowers the ppm by less than 40. My lame API tap water filter does better than that. Granted, my tap water TDS reading is only 100 give or take.

How many stages is your unit?

I know people that live in areas with really crappy water quality that run a little two little fishies phosban reactor with carbon in it, or just leave a chemipure elite bag in their top off water bucket.

 

[snakeblitz33]

Well, I think 500ppm TDS out of the tap is on a good day. I actually had the tap running for a little while before I took the reading. I think it would be higher then that if I didn't let the water run first.

My RO/DI unit is a five stage unit... there is one five micron sediment filter, one five micron GEM coconut carbon block filter and one 1 micron sediment filter - then it goes to the 100gpd RO unit membrane and then passed through the DI resin. ... five stages total.

I'm considering adding another two filter housings - one of them this catalytic carbon cartridge and the other a mix of GFO and GAC stuffed into an empty refillable DI resin housing.

The water around here is TERRIBLE!!!! I refuse to drink any water straight from the tap - but knowing that there is ammonia and 40ppm TDS coming out of the DI.... It looks like I might be drinking bottled water for a couple weeks while the new filters come in.

Back to basics... I'm going to set up this awesome filtration system in my house and then move and have no place to put it. lol

 

[snakeblitz33]

With 40ppm TDS coming off the RO membrane, do you think the membrane is shot too? Might have to order a new one, eh?

 

[bang guy]

Not necessarily. It really depends on what your tap has in it. The lower end RO membranes (like I have) only remove about 90% of silicates & phosphates. The 100GPD units are even worse. A TDS reading of 40 does not seem out of line with your tap reading 500 and using a 100GPD membrane. Have you considered stepping down to a 75GPD membrane?

 

[snakeblitz33]

I'll have to get the full statement of what is added to our local water supply when I can. Test tomorrow and all that...

I can go down to 50gpd if that helps! I don't really have to have a whole lot made up at one time, and if I can make 50g in a days notice, then I'm good. I wish that my tap TDS wasn't so high so that my filters would last longer. I guess they are working 5x more than BTLDreef's at 100TDS. Makes a lot of sense that I would have to change the filters out 5x more than her as well. Ugh, can't wait to get out of this city.

I can add a couple of carbon pre-filters to the system to cut down on the chloramines / chlorine / ammonia and change my filters and see if that cuts down the TDS some. I just now know why my systems haven't been doing well and it irks me that I discover it sooner. This won't happen again.

 

[snakeblitz33]

Bang,

I called the company up that I order filters from and they gave me a gold mine of advice.

They said that I shouldn't have to add additional pre-filters, that I just need to buy a filter pack with the catalytic carbon cartridge to take care of the chloramines in the water. The other thing was that they told me I should go down to a 75gpd unit with a 98% rejection rate. This means that my TDS should go down to about 10ppm coming out of the unit. Their little 10" DI filter resins can handle about 109 gallons at 10ppm before they start to become exhausted... and in my case, they told me that in order to have ZERO TDS water, I will have to change my DI resin out every 100 gallons. EEEK! I Wish my city had better quality water. It's a miracle, she said, that my TDS is as low as 40 right now with an exhausted DI and a 100gpd membrane.


So,... new filter pack
new membrane (75gpd)
and new flush valve

She also said that if I wanted to go longer between changes, that I could add a second or a third DI resign and change them out once every 200 to 300 gallons... and I could technically add a pre-filter softener to the system to remove calcium, magnesium and other stuff before it enters the membrane. She said that the cheapo $2 micron filters need to be replaced about once a month in my neck of the woods.



SO.... no wonder I am having problems. I told her that I have the 100gpd unit right now and she said that my TDS coming off of my membrane is about 50ppm currently.... which means that it exhausts any brand new DI filter cartridge every 24 gallons. EEEK!!!

 

[mr llimpid]

I'm glad I have a well and water softener then it goes threw the RO/DI unit. It still reads 0 on TD meter even after 6mo. Still change all pre fiters but only change DI when it turns black. I know you do just asking you back flush your unit every month?

 

[beaslbob]

Hopefully I'm not repeating stuff here--kinda skim read.

From what I have read is that water companies found they had to flush out their pipes and systems (daily) when they changed from chlorine to chlorimines.

Guess why?

Because it broke down in the pipes (to chlorine gas and ammonia) and causing the same aerobic bacteria in our tanks to bloom. Or the bacteria in the pipes actually broke down the chlorimines.

Either way the result was ammonia and resultant algae in the systems.

I have also heard chlorimines may be totally broken down by the time your water has traveled through the system and arrived at your house.

So your tap water can have ammonia in it or at least will have in a short while.

Even if the ro/di misses it, your tanks' bacteria and algae should consume that ammonia very quickly like in a matter of minutes.

After all the fish in your systems produce much higher ammonia continously.

still just my .02

 

[snakeblitz33]

Adding a half a gallon of .5ppm ammonia to a ten gallon tank full of sps corals is like dumping bleach in it on purpose. Our critters can take a lot of crap for sure, but th basics still has to be observed. I know there are places in the us that have very clean water, i just dont live in one of those places. Thanks for your insight, bob.

 

[beaslbob]

Quote:
Originally Posted by SnakeBlitz33 http:///t/396321/ammonia-in-my-ro-water#post_3530951
Adding a half a gallon of .5ppm ammonia to a ten gallon tank full of sps corals is like dumping bleach in it on purpose. Our critters can take a lot of crap for sure, but th basics still has to be observed. I know there are places in the us that have very clean water, i just dont live in one of those places. Thanks for your insight, bob.

And adding a 1/10 top off results in a .05 ammonia addition.

well below anything the fish are adding each hour.

But then I didn't have sps types in my system. Just softies and a heavy fish load.

And I had unmeasureable ammonia, nitrates, phosphates.

With untreated tap water.

still just my .02

 

[bang guy]

Snake, just going to a 75GPD may solve your issues. I disagree with the 100 gallons on the DI. It could be but it is completely dependent on what the contaminates are in your tap water. If my instincts are right, changing to a 75gpd (as I suggested) will considerably reduce everything except Silicates and Phosphates which a DI can handle effectively. If I'm right your TDS out of the RO will be 10 - 15 and out of the DI will be 0 - 2 and the DI will last 6 months or so. If I'm right, replace the carbon block and the DI every 6 months and the RO membrane every 30 months.

The TDS meter will know the truth so don't rely on me, just use my experience as a guide.

 

[snakeblitz33]

Bang, your experience is greatly appreciated, as always!

I did some more research. Looks like you are about correct on the figures. The 75gpd unit has a rejection rate of about 98%, making the water coming off of the membrane about 10TDS. I say about because according to the math, that's what it should be. Each DI resin is said to be able to take up 6,800ppm of dissolved compounds. At 10ppm coming off of the membrane, the DI should last about 680 gallons before having to be replaced, not the 100 gallons that I was originally told. Now, Sarah at AirWaterIce said that most of the time people can get away with about 1/4 of their DI exhausted before their TDS starts to creep up on them. I don't know how true this is - I'll have to test it.

I am considering in the future adding two extra pre-filters to the system... one 5 micron sediment filter that gets changed regularly (always have the filters on hand) and the other is a soft water filter, which removes calcium and magnesium before it goes through the membrane, thereby increasing the life of the membrane. I know one thing is for sure - I was doing all of that completely wrong and now that I feel more educated on the subject, I am kicking myself for not spotting it sooner.

That company sells a 5lb bag of DI resin for about $50, and it will fill up 4.5 containers of DI before its useless.

 

[2quills]

I don't know if this helps, Seth. But I just picked up a 75gpd 6 stage unit with the dual D.I. So far I've filled my main system (approx. 165 gallons), a 55g quarantine tank and have made about 100 gallons worth of mixed and top off water. So I'd say I've produced about 320 gallons or so from the brand new unit. It's 2 months old. I still get 0 TDS coming out of the dual D.I. but the TDS from the membrane has steadily risen. Now when I first turn the unit on the TDS reads about 60, then it slowly drops over the course of about an hour and levels off some were in the 20's for now.

But I'm already close to the point where I'm about ready to replace the carbon and sediment. I may refill my first D.I. canister as well but I think I'm going to wait and see how long it takes to start seeing some measurable TDS just out of curiosity.

 

[bang guy]

That reminds me of a good point. The water that comes out of an RO first with be a lot higher in TDS than after it has run for a minute.

In other words, it's a LOT better to fill up a 30 gallon container in a single run than it is to fill up 60 1/2 gallon containers with a pause between each.

 

[snakeblitz33]

Hmm, that's why it's best to buy water from a place that has the RO unit constantly going...

Makes a lot of sense.

I ran some figures. At the current rate, it will cost me $500 a year to properly maintain my RO/DI unit at my current rate of consumption. It will cost right at $0.09 per gallon.

I ran some other figures as well to run a commercial unit, and it looks like the more you run it / the more gallons you get out of the unit, despite DI refills, the lower the cost is per gallon of water. Kinda neat.

 

[2quills]

Yeah I think it's one of those things that the more you use it the more efficient it runs.

I will say that when I first turn on the unit I get a fairly sharp drop in the TDS within the first 5-10 minutes. Then the longer it runs the slower the TDS out of the membrane drops. Admittedly, I do have a flush kit installed on it but I have not kept up with the recommended flushings between usage based on the volume of water you produce and not so much the amount of time in which you've had the filter media in the filter. I'll probably make a new batch this weekend and I'd really like to give the unit a good flush and see what the difference is from the last time. I believe this process can also be automated. Membrane performance from what I understand can very pretty dramatically depending on how you maintain the unit.