An important part of maintaining an aquarium is keeping track of its pH levels.
This amount denotes the acidity or basicity of the tank water.
As an aquarist, it is important to know the importance of tank water pH levels to the health of the whole aquarium itself.
In fish only setups, pH levels may be of lesser importance as long as it does not fluctuate or drop below 7.
8 but in reef aquariums, it can be a make or break factor.
The pH of a substance generally denotes the capacity of hydrogen (H+) ions to react.
Lower pH readings mean greater concentrations of H+ in a substance.
This amount is often associated with levels of hydronium (H3O+) ions in a substance.
In pH readings greater than 7, most of the H3O+ bond with hydroxyl (OH-) ions and there is an excess in (OH-).
In pure water at 22°C (72°F), hydronium and hydroxyl ions exist in equal quantities; each with a concentration of 1 x 10-7 moles/liter.
In measuring pH levels 7 is the midpoint.
Substances with a pH of 7 are neutral.
Substances with pH readings lower than 7 are acids with acidic strength increasing the lower the number.
A pH reading greater than 7 indicates a base, the opposite of acids.
Bases react to acids to neutralize them.
In the case of hydronium and hydroxyl, neutralization produces water (H3O+ + OH- => 2H2O).
To measure the acidity or basicity of saltwater, you can use different methods.
First off is by using a pH meter.
Unfortunately, pH meters are calibrated at a specific temperature and pH readings of a particular substance changes in accuracy the farther you get from the calibration temperature.
Most pH meters are calibrated at room temperatures but you can find pH meters calibrated close to your tank's average temperature.
Another method is by using a pH sensitive strip.
This is readily available in most chemical stores and pharmacies.
Most of these strips can only measure in narrow ranges of pH, though.
Make sure you get the range you need.
Arguably, the most accurate way to measure pH is by titration.
In this method, a base with known acidity is added to a sample until all acids are neutralized.
The amount of base used will correspond to the amount of acids in the substance and therefore, its acidity.
Measuring pH levels should be done at least once a day.
If you sense something odd happening in your aquarium, such as your fish gasping for air more often, testing water pH together with other tests will help you determine if there is a problem.
Especially in reef aquariums it is important to keep track of the tank water's pH levels regularly.
In a saltwater fish only setup, acute pH changes are sometimes more important than the pH levels themselves.
This is because saltwater fishes get stressed very fast in changing pH levels.
In short, a stable pH 7.
9, although low, could be better than an 8 changing to 8.
2 in a matter of hours then back to 8.
0.
Invertebrates and corals also abhor low pH levels.
Invertebrates will often die when pH drop below 8.
They will also have problems making their exoskeletons in low pH.
If nothing can be done to avert low pH in your tank, you should at least keep calcium concentrations from 400 to 500 parts per million.
In the oceans, pH levels rarely fluctuate.
It is quite stable in a level range of pH 8.
0 to 8.
3.
It is therefore ideal to keep pH levels of your saltwater aquarium within this range.