High Ph 8.5

[shoddyk]

I am having a problem with my ph again. I checked it three different ways and they all read the same. My PH reading is 8.5. What could be causeing it to go up. I have a 125 gallon reef with 200lbs of liverock, 2 x 20gallon refugiums with macro, 60 gallon sump all running. I keep the lights on the 2 refugiums 24 hours a day also. Any sugestions?

ph-8.5
po4-.5
no3-10
no2-.1
kh-4meq/l
nh3-0
ca-420

 

[steve the plumb]

Are you using kalk for evaporation

 

[bertoni]

A high-pH supplement might be an issue. The refugia can also drive up the pH by consuming CO2 from the water.

 

[Randy Holmes-Farley]

IMO, pH 8.5 as the max is fine. Mine often hovers there.

This article has more:

High pH: Causes and Cures
http://reefkeeping.com/issues/2005-03/rhf/index.htm

 

[shoddyk]

High PH again

High PH again

My PH is getting higher again. Could my two refugiums be sucking all the co2 out of the water and driving the PH up. Yesterday I added vineger to lower the PH down to 8.2 and today it is back up to 8.6. Is it because all of the macro and Plants? My water reading are perfect except the high ph.

 

[shoddyk]

I have increased my co2 flow from the calcium reactor and still no change.

 

[shoddyk]

So, what do you think? My shaving brush in the tank on the right have non stop bubbles coming from them now. Why are the shaving brush creating bubbles?

 

[bertoni]

Hmm, well, photosynthesis could be an issue. What are you supplementing for alkalinity?

 

[Randy Holmes-Farley]

Aside from high pH additives, it is photosynthesis, whether in the main tank or a refugium, that can drive up pH.

Rarely is high pH a problem without high pH additives, but aeration, if adequate, will always serve to bring the pH down.

To be honest, 99% of the high pH problems reported here where high pH additives were not used turn out to be measurement errors. How are you measuring pH?

 

[shoddyk]

I am not supplementing anything for alk. My Alk is staying at 200 and not moving. I am testing it with 2 different test kits and they are both reading the same thing.

 

[Randy Holmes-Farley]

pH test kits are often not very reliable, IMO, and I would not do anything drastic based on a high pH (>8.5) reading with a kit. However, with the alkalinity that high, the pH at perfect equilibration with normal air will be about 8.4, so it is not too surprising that it may get a little higher during the day. More aeration can bring it down, as can additions of soda water (CO2) and/or vinegar as described in the article linked above.

 

[shoddyk]

I added vineger a few days ago and it went down. Is adding a half bottle of vineger a day going to harm the chemistry of the water at all?

 

[Randy Holmes-Farley]

It will drive bacterial growth. That might use up some nutrients, if you can export the bacteria some how (maybe skimming), but it also uses O2.

 

[Fastmarc]

Be careful with the vinegar as that bacterial 'bloom' can be more than a little annoying. It will also grow in your pipes and slow down your flow.

 

[shoddyk]

I am going to shorten the time I keep the light on the refugiums and see how that goes. Thanks for all the helpful info Randy.

 

[Fastmarc]

I'm also plagued with higher than desired ph, but I have stopped worrying about it for years and the inhabitants do not seem to be bothered by it.
Based on my experience, I wouldn't use the vinegar as a long term solution.

 

[shoddyk]

It doesn't seem to have any effect on anything in my tank either. In fact since it has been high, the corals are really opened up more than normal.

 

[Randy Holmes-Farley]

Thanks for all the helpful info Randy.

You're welcome.

Good luck.