Quarantine RODI Wastewater

[bradbmbj]

I have been using the wastewater from the RO for my Qt for at Least two years with no problems, I happened to mention this to a LFS employee and he seemed real concerned, My thoughts are that the water will have higher levels of nutrients and such, maybe even some things worse than that , but how does this differ from someone who uses tap water? Some people use tap water and top off with tapwater, so the water in the tank continues to get more concentrated with pollutants, but usually all that happens is an algae problem. Besides concentrating 5 gallons into four really isn't that bad to me. What are your thoughts?

 

[davewbush]

IMO its worse than tap water because with all the good water taken out the waste has higher cosentration off bad things in it.

 

[CSoli921]

^ +1

 

[bradbmbj]

yes, but when the tank water evaporates all those minerals and pollutants stay in the tank, then when you top off you add more, over the course of just one week of topping off with tap water you would have introduced far more than what the ro produces

 

[davewbush]

I think most ro's do about 5 to 1. Five bad gallons to 1 good gallon. So if you top off with 10 gal of tap water, 10 gal of ro waste water would be equal to 12 gal of tap water.

 

[bradbmbj]

Additionally the waste water has been through the sediment and carbon block which will lower chemical levels.

 

[theredben]

Does anyone actually have any reasons not to do this, besides speculation?

bradbmbj, If you have been doing this for 2 years with no problems, more power to you. I say if this is what it takes for you to actually QT, it is better than not QTing anything. As long as you are doing somewhat regular water changes, then the level of "pollutants" will stay quite low.

 

[davewbush]

You might want to post this question in the reek chemistry fourm. They will be able to answer it better for you. What works for one may not work for the next in this hobby.

 

[bradbmbj]

I can definitely use pure RODI, but I see no reason to use my ro filters for this when I can just use the waste water that I accumulate from the display tanks water, and I do change 5 gallons every two days in my 20 gallon Qt

 

[dwd5813]

i measured tds of my tap and waste a while back and the waste was higher despite having gone through sediment and carbon filters. someone on here seemed very confident that the majority of that tds was calcium but i'm not as sure as he was. anyway, i wouldn't use wastewater for any of my tanks, especially a qt.

 

[davewbush]

Are you talking about using the ro waste water for water changes on your qt or your dt waste water for water changes.

 

[luther1200]

I would say anything you are putting in a QT tank is in need of special care. So you would want that water better than your DT. The TDS from RO WW is higher than tap.

But if you really want to use it, check the PO4,, and NO3 levels. If they are good I guess you would be O.K. But if it were me I wouldn't do it, sooner or later the WW contaminents will build to unexceptable levels IMO. And RO/DI water is cheap enough to make I don't see the big deal in making more for a 20g tank. If you want to use your WW for something try the laundry or watering the yard.

 

[THE ROOK]

No need to subject your fish to garbage water, imo. Your want healthy fish but placing them in water that could be high in chlorine & other chemicals. Pre-filters do very little for tds most of that work is done thru the membrane & di resin.

Seems to me it would be much better for the fish to get a 5 gallon water change once a week with pure water than every two days with garbage.

Are you using some sort of filter in the qt?

 

[bradbmbj]

Why is the water "garbage"? Because its called waste water? Why would a higher silicate, phosphate, or calcium content effect fish? The RO does nothing for chlorine, chlorimines, or any other chemicals. Why would someone with a reef using tap water top offs be in better condition than me using carbon filters on the QT? The ro and does nothing for chemical filtration, it is mechanical. Why would my 130 to 150 tds before ro be worse than someone who uses strait tap with 400 tds? My QT is set up more like a display, I can not for the life of me understand why people use barebottoms with a sponge as all the filtration. I have 1/2 inch off sand that I siphon upon water changes and about 8 pounds of rock with a cave, I also run a hang on back filter. with this method I have never had an ammonia issue, but I change water often to be sure. I do however use some medications when needed that does kill off some bacteria,but I continue with the with the water changes, never had a problem. I feel that this has to be better for the fish rather than being thrown into a plain glass box with a piece of pvc. I am not trying to argue that this is the way to go, as davewbush said "What works for one may not work for the next in this hobby" but I am looking for evidence. Has anyone else actually done this and have had problems? Please do not take me wrong, I take very good care of my fish and I am not to cheap to use all ro water, its pretty cheap anyway. I just would like to see more facts on the matter than paranoia over a higher tds.

 

[CHOMPERS MFK]

Re: Quarantine RODI Wastewater

<a href=showthread.php?s=&postid=14659627#post14659627 target=_blank>Originally posted</a> by bradbmbj
I have been using the wastewater from the RO for my Qt for at Least two years with no problems, I happened to mention this to a LFS employee and he seemed real concerned, My thoughts are that the water will have higher levels of nutrients and such, maybe even some things worse than that , but how does this differ from someone who uses tap water? Some people use tap water and top off with tapwater, so the water in the tank continues to get more concentrated with pollutants, but usually all that happens is an algae problem. Besides concentrating 5 gallons into four really isn't that bad to me. What are your thoughts?

The main factor is what the water is like to start with. Since you have been doing it for two years without any problems is enough to show that you have pretty good water. If the QT is for fish only then there should be no concern. Either way, I agree with you that the concentration from tap water is largely insignificant. Through my recent research, I have found some information (not published by RO manufacturers) that stated that the waste water was 4-8 gallons per gallon produced, depending on the system and how old the membrane and pressure.

Anyway, since it works there is no point in changing. I can understand people not agreeing because what is engrained in their brains, and this goes against what they know. But whatever works...

 

[CHOMPERS MFK]

<a href=showthread.php?s=&postid=14660214#post14660214 target=_blank>Originally posted</a> by dwd5813
i measured tds of my tap and waste a while back and the waste was higher despite having gone through sediment and carbon filters. someone on here seemed very confident that the majority of that tds was calcium but i'm not as sure as he was. anyway, i wouldn't use wastewater for any of my tanks, especially a qt.

Measure it again if you don't mind and see if it they are around 20-25% of each other. The waste should actually be less than a 25% increase considering part is removed in the carbon etc. Sediment shouldn't show up on the TDS meter because it is suspended rather than dissolved, but what is removed by carbon and resin beds (if applicable) should be enough to show up.

If you wouldn't mind doing this and then posting the results here, it would be really interesting to know.

Total hardness is the majority of the TDS and calcium is in fact the majority of the total hardness. Calcium should account for around 80% of your TDS. You can get a full breakdown of your water from your water company. Find their website and they will have the latest water tests or a full history.

 

[dwd5813]

i think i wrote it down. hang on and i'll check

 

[luther1200]

I wouldn't go compairing some one who uses tap water for a reef to what you want to do. Just because people ignorantly use tap water for a reef doesn't mean thay will not have problems(algae issues, high PO4,). And even if the majority of the WW content is Ca., you don't want to much of that either. You can overdose on anything if it gets out of balance.

There are always ways around "the rules". You may just have excelant source tap water. Which would be my guess as to why you haven't had any problems yet.

What is your tap water TDS? PO4 level?

 

[dwd5813]

i did several tests of each and averaged them out.
avg tap tds - 312
avg ww tds - 384

so, around a 23% increase. it was not as dramatic as i thought it would be, but enough to tell me that i would be better off not using it.

 

[Kenmx10]

I think we need to consider the whole purpose for using RO/DI water. Its for the health of the fish. We want our $125.00 purple tang to be nice and healthy, so he can fight off the tramma we put them through by snatching them out of their naturally balanced, environment and sticking them in a box. Healthy fish are less likely to get parasites, infections, death, etc.

Im still not exactly sure what the intentions are. Is it just to use the water because you can? Or are you trying to save money on filters? Are you worried about your water bill?

Carbon and sediment filters are pretty cheap. And if you change them out regularly as needed, Your RO filter should last a long time, giving your fish plenty of health water. The RO filter does the bulk of the work. Bye pass it and you never know what you are really getting. Unless you do a lab test on your tap water every time you use it. That will cost a lot more than a sediment filter( 2-3 dollars)

As far as your water bill , It may be the difference in one or two showers, maybe .50 cents a month or so.

If it were me, I would be more worried about the $125 Tang, $70 Angle, $60 Butterfly, etc.... But you never know, They may do just fine. I quess thats just a chance one has to take....