R/O WATER MIXED WITH TAP

[MrCBS]

I was wondering if there was a rule of thumb mix ratio for R/O and Tap water. I R/O about 20gals of water at a time and have been told I need to add tap water to it to keep the PH from crashing. My PH from the tap is about 8.2 and from the R/O is about 6.8. I aded about 1/2 gal of tap to the R/O but even after agitating it for 12 to 24 hours the PH drops over night in the tank. Do I need more tap water?

[Dkarc@Aol.com]

Well first off, why are you using r/o? If not using it for breeding then it is a waste of money/water. If you are breeding then you need to get yourself a good digital water hardness meter. You can get some for fairly cheap (under $100, or less). If you are breeding then you want the hardness of the water to be no more than 120 ppm. Yes, you do need to add back minerals into the r/o water to keep the pH stable and to bring the hardness up some. If it is too low, the pH will crash due to a lack of KH in the water. There is no standard amount of how much tap to add back in as it depends upon the hardness of your tap water. Some people may need it a 50/50 ratio, while others only need a 25/75 ratio. It totally depends upon the hardness. You can get by with standard hardness kit you can get from a LFS for now, but if your using r/o everyday, I would just go ahead and buy a meter as it will save a lot of time and hassle.

-Ryan

[MrCBS]

Thanks for the come back Ryan
I just recently bought a hardness/temp meter and of course the R/O water is about 2 or 3 at 82 degrees.
So your saying I need to add tap water until the tds's read 50 to 120 and don't worry about where the PH ends up?

[Carol_Roberts]

Yes, you need more minerals. As Ryan said, GH and KH are the numbers you need to know.

Remind me - isn't your water naturally low in minerals? IF so extra tap will not help. Experiment . . . Try 10 gallons of tap to 10 gallons of RO and and see if pH stabilizes. Your pH may still be close to 8. Does your water company add buffer to raise alkalinity of your tap water to protect water pipes?

[MrCBS]

Hi Carol
Yes my GH & KH are 8 to 12 out of the tap . I have a home water softener which may be part of my problem. I'm not sure how much that effects my water chemistry. I checked my tanks when I recv'd my meter and found a couple at 997ppm and a couple at 780ppm. I suspect this is from adding R/O Right chemical to the R/O water without a meter. Now I have it at 35-50ppm and have lowered to tanks down to about 120ppm. I seem to still have problems with my PH dropping even thought I do w/c every other day 25 - 50%. I haven't tryed a 50-50 tap/Ro mix to see if that stabilizes my PH.
I think this PH wandering is stressing my pairs and keeping them from breeding. I'll do a water change...they'll start cleaning the breeding cone and then wander off.
Do you know of any Discus that talk ;D it would be so much easier if they could tell me what they want.
Thanks
Chris

[Carol_Roberts]

I'd try 50% regular water (prior to the water softener) and 50% RO.

[MrCBS]

Thanks I'll give that a try. Also when I said my GH & KH was 8 to 12 I meant it took 8 to 12 drops to change my test tube water.
thanks again
Chris

[Carol_Roberts]

Either your water source varies or your test kit is old

[Hilroy50]

If you are on a well, the water hardness will vary depending upon conditions. I notice at the end of Aug and all of Sept my well water is harder than any other time of year. I currently am using 3gal well to 5 gal RO, this is giving me about 120ppm GH

[GulfCoastDiscus]

Hi Mrcbs,
Are you using the RO/tap mix for breeding?
Because if you are the PPM should be between 40ppm and 60ppm. That's 80 to 120 Microseimens. You also need to reduce your PH between 5.5 to 6.5. This is for breeding.

Dan

[Cosmo]

Hello Chris,

Been meaning to write and ask how things are going. When I first started using RO I had persistent crash problems as well, very similar to what you're describing. Found that Kent PH Stable solved this problem and keeps my ph very steady .. haven't had a crash since I started using it.

It does however, add to your TDS, and increases the Ph so remember to factor that in. Could make it difficult to achieve the parameters Dan provided for your breeding tanks.
Jim