Low PH URGENT HELP

[roy123]

I have been struggling to raise my ph for the past few weeks... my ph is so low that almost to an unacceptable point, today it even drop to 7.6..... usually it around 7.8 I have used the Kent marine buffer every other day and useless; I have performed weekly water change then recently three day water change, around 10%~15%.... and the ph didn't raise a bit...Last week I stop use the buffer and performed a 50% water change until now, the ph didn't raise a bit. I even tested the new mixed water with ph only 8.0, and it will decrease to 7.8 over night...Now that I thinking if there's something's wrong with my salt? I use:
RO water
Instant ocean salt
ammonia 0
nitrite0
nitrate less than 10
temperature 79
This is a 6 months old fish only thank with some live rock.

 

[broomer5]

Are you aerating the RO water overnight prior to mixing the Instant Ocean ?
This is more important than many people realize.

 

[beaslbob]

My daytime ph had fallen to 7.4 and new fish were not surviving longer than three weeks. They would eventually develop white spots, start breathing heavy, move erratic and slow, and then die. Buffers would raise the daytime ph to 8.2 but the next week it was back down again.
Currently my ph still falls to 7.8 at night just before lights on.
I added macros to my display and the daytime rose and stayed above 8.2 without adding buffers. That was about a year ago. Since then a yellow tang, originally very sickly, has fattened up and trippled in size. Also have added about 5 fish all of which have thrived for at least 4 months.
ph drops start with carbon dioxide. What I highly suspect in my system was the fish load had gotten to the point where carbon dioxide had built up. So not only was the ph dropping, but the fish were probably sufficating from the carbon dioxide. When the plant life was added, it consumed the carbon dioxide in the daytime and the rose. And the fish thrived.

 

[broomer5]

I even tested the new mixed water with ph only 8.0, and it will decrease to 7.8 over night
Roy - what you mentioned here is why I asked whether or not you aerate your RO water. It's true that CO2 can cause a drop in newly mixed saltwater. CO2 gas in solution in the tapwater - passes right through an RO membrane ( whether you make the RO or purchase it ). RO membranes are great for removing solids and minerals, ions ..... but the CO2 gas is so small that it moves right through. Plus if you have CO2 gas in solution, you have carbonic acid as well.
If there is an unusual high concentration of CO2 gas in solution in your RO water - it WILL drag down your pH.
Have you tested your pH of your tapwater - before and after the RO ? You'll need a freshwater pH kit, or electronic pH probe/display.
I've had conversations with tech help at Aquaium Systems - makers of Instant Ocean. After discussing my similar experiences with them - they recommended I aerate the RO freshwater overnight prior to mixing the saltmix.
This cured my pH problem on newly mixed IO, and it measured at 8.2 - 8.3

 

[roy123]

when you mention aerating is that means expose the water to oxygen? I have left my bucket lid open for quiet sometime b4 mixing the salt...if the problem caused by CO2; is adding a ozonizer will help?? what about an air pump???
Thanks

 

[attml]

If you are having problems raising the PH even after airating and extended mixing of the salt you can try dripping kalk. Sometimes my PH drops because of excess CO2 from my calcium reactor. When I get a dip in PH I just drip a little kalk and it always brings it back up.

 

[neoreef]

Hi Roy,
Water will absorb oxygen from the air only if it is exposed to it. The more surface contact, the more absorption takes place. Leaving the lid off will only expose the top layer of water to the air. Once it has absorbed all the oxygen it can, no further absorption takes place in the layers of undisturbed water below the surface.
Probably he means to put an inexpensive powerhead in the bucket and get the water stirring, and if you have a venturini tube on the powerhead get that working also.
HTH
Kathy

 

[roy123]

Thankz too all you guys