How to raise PH?

[nikonosis]

We have had a 12g nano cube running for 8 days now.
There is one piece of base rock and lots of rubble with coraline on it, the sand is caribsea speacial reef grade.
Nitrite 0
Nitrate 0
Amonia 0
Phosphates 0
Calcium 440-460
Ph is 7.8

What is causeing the PH to be 7.8 and what can we do to raise it?

 

[Abysswater]

It could be your salt mix. Measure it after making a batch after 24 hours and see waht it is. If it is low add some kent buffer or other brand to your liking. just pre mix it with your new water or your evap water. Plus double check your test kit with another or LFS.
Remember if you turn off your lights at night the PH will drop and rise during the day.

 

[nikonosis]

im using Instant Ocean. Shouldn't it be around 8.2?

 

[Paintbug]

happen to know what you alk levels are? be carefull when using buffers. most will raise the alk levels along with it!

heres an article on low PH:
http://www.reefkeeping.com/issues/2004-09/rhf/index.php

 

[nikonosis]

no i don't have an alkalinity test.

 

[Paintbug]

may want to pick on up or get your LFS to check it for you. 7.8 PH is the low side of safe. but ideal conditions would be 8.2. theres several causes of low PH that article covers them all. could be something as simple as alittle more surface agitation.

 

[nikonosis]

<a href=showthread.php?s=&postid=6677788#post6677788 target=_blank>Originally posted</a> by Abysswater
It could be your salt mix. Measure it after making a batch after 24 hours and see waht it is. If it is low add some kent buffer or other brand to your liking. just pre mix it with your new water or your evap water. Plus double check your test kit with another or LFS.
Remember if you turn off your lights at night the PH will drop and rise during the day.

"Buffers alone are not generally a good method as they raise pH little, and result in excessive alkalinity. Unfortunately, the labels on many commercial buffers are written in ways that convince aquarists that the pH will be fine if they just add some buffer. More often than not, the pH is not improved for more than a day, and the alkalinity rises beyond desired limits."

 

[nikonosis]

<a href=showthread.php?s=&postid=6677843#post6677843 target=_blank>Originally posted</a> by Paintbug
may want to pick on up or get your LFS to check it for you. 7.8 PH is the low side of safe. but ideal conditions would be 8.2. theres several causes of low PH that article covers them all. could be something as simple as alittle more surface agitation.

there is macro algae in the back of the tank so the CO2 thing can't be a reason. I really can't see anything causing it other than alkalinity is low. If it is low, what should I do to raise it? I have been dosing purple up for about 3 days now btw. The ph was 7.8 before doing that.

 

[Paintbug]

just because you have macro algae in the tank doesnt mean you wont have a CO2 problem. you still need aeriation. does your tank have a hood? is it an open hood? if not you may not be getting enough fresh air into the hood. but, seeing you have started using purple up. and thats when the problems started. i would say your alk being low is the cause.
From the article:
"Low pH Due to Low Alkalinity

Low alkalinity can also lead to low pH. For example, if alkalinity is not supplemented as fast as it is removed by calcification, the pH will likely drop. This drop will occur with all alkalinity supplementation schemes, but will be most observable when using schemes that do not themselves raise pH (like CaCO3/CO2 reactors or bicarbonate). In this situation, the obvious solution is to somehow add more alkalinity (as shown in Figure 4)."

another article on Alk:
http://www.advancedaquarist.com/issues/may2002/chem.htm

it may be time for you to start looking into a 2 part additive for the tank. something like B-ionic works great. and for a 12g tank it wouldnt be extremly expensive. you can make your own as well really cheap, which is what i do. the 2 part system makes keeping your alk and calcium in balance really easy.

 

[nikonosis]

<a href=showthread.php?s=&postid=6678240#post6678240 target=_blank>Originally posted</a> by Paintbug
just because you have macro algae in the tank doesnt mean you wont have a CO2 problem. you still need aeriation. does your tank have a hood? is it an open hood? if not you may not be getting enough fresh air into the hood. but, seeing you have started using purple up. and thats when the problems started. i would say your alk being low is the cause.
From the article:
"Low pH Due to Low Alkalinity

Low alkalinity can also lead to low pH. For example, if alkalinity is not supplemented as fast as it is removed by calcification, the pH will likely drop. This drop will occur with all alkalinity supplementation schemes, but will be most observable when using schemes that do not themselves raise pH (like CaCO3/CO2 reactors or bicarbonate). In this situation, the obvious solution is to somehow add more alkalinity (as shown in Figure 4)."

another article on Alk:
http://www.advancedaquarist.com/issues/may2002/chem.htm

it may be time for you to start looking into a 2 part additive for the tank. something like B-ionic works great. and for a 12g tank it wouldnt be extremly expensive. you can make your own as well really cheap, which is what i do. the 2 part system makes keeping your alk and calcium in balance really easy.

I would probably get some oceans blend from a LFS here. The hood is always closed on the tank but there are 2 fans on it...

 

[Paintbug]

oceans blend?