Low pH?

[hopperjl16]

I'm getting my biocube 29 going and have been checking parameters every couple days (no creatures in it yet, just live rock and live sand). everything seems perfect (ammonia, nitrate, nitrite all zero, SG 1.024), but my pH is only 8.0. Is this too low? I'm supposed to be around 8.2-8.4 correct? I'm about to add my cuc and a couple mushrooms in a couple days. Will the pH change a little once I start getting stuff in the tank? Or do I need to adjust it now before I start putting things in?

Thanks!
Jaime

 

[Tahoe61]

To get an baseline pH value you should test pH the same time of day each time. pH will be it's lowest in the am before the lights go on, the higher value will be at the end of the photo period. A pH of 8.0 is acceptable for the corals and cuc you want to add, no intervention is needed at this time.

Test though a couple times to see what the difference in the pH between the am value and the pm value, you want to avoid swings.

Creating more surface agitation with the use of a power head can sometimes promote a higher value.

 

[AllSignsPointToFish]

My tank pH routinely runs 8.0-8.1 with no apparent ill effects on tank inhabitants. In fact, I can't seem to get my tank pH above 8.1,

Some folks with calcium reactors even successfully run tanks with a pH around 7.8. I think you'll be fine with a pH around 8.

 

[hopperjl16]

Thank you! I had no idea about the time of day thing. I do have one power head going.

 

[Randy Holmes-Farley Verified Community Expert]

I'm getting my biocube 29 going and have been checking parameters every couple days (no creatures in it yet, just live rock and live sand). everything seems perfect (ammonia, nitrate, nitrite all zero, SG 1.024), but my pH is only 8.0. Is this too low? I'm supposed to be around 8.2-8.4 correct? I'm about to add my cuc and a couple mushrooms in a couple days. Will the pH change a little once I start getting stuff in the tank? Or do I need to adjust it now before I start putting things in?

Thanks!
Jaime

pH 8.0 is fine.

I discuss optimnal parameters, including pH, here:

Optimal Parameters for a Coral Reef Aquarium: By Randy Holmes-Farley

from it:

pH

pH is a measure of the concentration of protons (H+ ions) and hydroxide (OH-) ions in the water. Aquarists spend a considerable amount of time and effort worrying about, and attempting to solve, apparent problems with the pH of their aquaria. Some of this effort is justified, as true pH problems can lead to poor animal health. In many cases, however, the only problem is with the pH measurement or its interpretation. Moreover, the maintenance of appropriate alkalinity in seawater goes a long way to ensuring that the pH is acceptable, with just a couple of exceptions that will be discussed below.

Several factors make monitoring a marine aquarium's pH level useful. One is that aquatic organisms thrive only in a particular pH range, which varies from organism to organism. It is therefore difficult to justify a claim that a particular pH range is "optimal" in an aquarium housing many species. Even natural seawater's pH (8.0 to 8.3) may be suboptimal for some of its creatures, but it was recognized more than eighty years ago that pH levels different from natural seawater (down to 7.3, for example) are stressful to fish. Additional information now exists about optimal pH ranges for many organisms, but the data are inadequate to allow aquarists to optimize pH for most organisms which interest them.

Additionally, pH's effect on organisms can be direct, or indirect. The toxicity of metals such as copper and nickel to some aquarium organisms, such as mysids and amphipods, is known to vary with pH. Consequently the acceptable pH range of one aquarium may differ from another aquarium, even if they contain the same organisms, but have different concentrations of metals.

Changes in pH nevertheless do substantially impact some fundamental processes taking place in many marine organisms. One of these fundamental processes is calcification, or deposition of calcium carbonate skeletons, which is known to depend on pH, usually dropping as pH falls. At a low enough pH (somewhere below pH 7.7) coral skeletons can begin to slowly dissolve. Using this type of information, along with the integrated experience of many hobbyists, we can develop some guidelines about what is an acceptable pH range for reef aquaria, and what values push the limits.

The acceptable pH range for reef aquaria is an opinion rather than a clear fact, and will certainly vary with the opinion's provider. This range may also be quite different from the "optimal" range. Justifying what is optimal, however, is much more problematic than is justifying that which is simply acceptable, so we will focus on the latter. As a goal, I'd suggest that the pH of natural seawater, about 8.2, is appropriate, but coral reef aquaria can clearly succeed 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 aquaria.

In truth, many aquarists never measure pH, and many that do so do not do anything with the results they obtain. This lack of action is usually okay, as most aquaria do not naturally fall outside of the acceptable ranges. Times when it is most important to at least check pH once in a while are:

1. When using very high pH additives, such as limewater (kalkwasser). In this case, one should ensure that the pH does not get above about 8.55. At higher values, the precipitation of calcium carbonate on pumps and such can become excessive. Every 0.3 pH unit rise in pH is equivalent to about a doubling of the calcium or alkalinity value in terms of the likelihood of precipitation of calcium carbonate (because bicarbonate turns into carbonate as the pH rises, driving precipitation). Aquaria may often get to a pH that is high enough to double the precipitation rate due to elevated pH, but one does not often see aquaria with calcium or alkalinity that is double the normal value, making high pH a big driver of precipitation.

2. When the air around the aquarium has elevated carbon dioxide levels, such as in a newer, tighter home. Low pH due to elevated carbon dioxide in the air is VERY common. While it may be useful to ensure the pH stays above 8.0, there are many fine aquaria with the bottom end of the pH range at pH 7.8. Below that value, I'd want to take more aggressive action, such as more fresh air in the home, top off with limewater (kalkwasser), a fresh air line from outside to a skimmer inlet, or a CO2 scrubber on a skimmer inlet.

 

[Deberber]

I also have a biocube 29. My ph ran at around 7.9-8.0. If you have the HQI version I have found the removing the black covers over the sump will raise the pH, even if just for 30 minute periods. It now runs at around 8.1-8.3

 

[AllSignsPointToFish]

I have never gotten my pH over 8.1, regardless of what I do. Alkalinity is fine, and I even temporarily plumbed in outside air to the skimmer, yet the pH stays constant. I guess that's a good thing