pH question

[TheNorthernLight]

Hello,

 

On a 20G systems, is it normal for pH to go from 8.33 at midnight to 7.88 by 10am ? Or do I need to add buffer solution?

 

thanks,

 

spyrule

[Gwoardnog]

That's a pretty hefty swing. Check or Ca. and alk. chances are somethings out of whack.

[Cooper8768]

just ckeck your alk (dKH). ph swings are a sign of low dKH. if you have a sump then you could also put the light on a reverse cycle. this also helps with reducing CO2 build ups. Which is the major player in your ph swings at night. You can also switch to a reef salt mix. IMO they seem to have better buffers then FOWLR suggested salts. Never add any supplements unless you test for it. when you mess with the dKH you can crash a tank fast, if you dont know what you are doing.

[TheNorthernLight]

yeah,

 

I actually DO test for Alk, Calcium, Amonia, the nitr(i)(a)tes.

 

The only reason I found the swing is because I just got a reefkeeper2, that has a pH sensor built in, and now I'm able to read the difference.

[cmador]

I wouldn't get too caught up in ph readings - as long your readings are consistant and the tank looks well - I wouldn't mess with anything. When I first bought my ph monitor, I too was suprised at the drop overnight (8.18 - 7.85), but I had the tank up and running for six months without any problems so I decided not to create any. Just keep up with your weekly water changes using a quality salt mix and your tank will be just fine. HTH

[MrAnderson]

Repost from General Discussion a few days ago...

 

Here's a quote from Eric Borneman's Aquarium Corals:

 

On the reef, the daily cycle may take pH as high as 8.5 during the day, and as low as 8.0 at night, and the aquarist should always note the time of day when taking pH readings before becoming alarmed

 

from: http://www.advancedaquarist.com/issues/june2002/chem.htm :

 

As a goal, Id suggest that the pH of natural seawater, about 8.2, is appropriate, but tanks can clearly operate in a wider range of pH values. In my opinion, the pH range from 7.8 to 8.5 is an acceptable range for reef tanks, with several caveats.

 

low pH problems are those where the pH is below 7.8. That is, where the daily pH low drops below 7.8. Of course, if the pH hits 7.9 you may still want to raise it, but the need is not so immediate.

 

High indoor carbon dioxide can also apparently lead to low pH problems in many tanks. Many aquarists have found that opening a window near the tank can result in a significant rise in pH within a day or two.

[TheNorthernLight]

hmmm, thats seriously interesting info...

 

Thanks MrAnderson.

 

spyrule =out=

[TheNorthernLight]

Here's some other interesting info...

 

just did a salifert test for dKh and Alk.

 

dKh = 8

Alk = 2.62(ish)

 

Essentially... exactly what ocean water is !!!.

 

I'm still stumped.