PH Wiki Entry

dallasg

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I cant add to the wiki, still a work in progress

What is PH
pH is a measure of the acidity or basicity of a solution. It is defined as the cologarithm of the activity of dissolved hydrogen ions (H+). Hydrogen ion activity coefficients cannot be measured experimentally, so they are based on theoretical calculations. The pH scale is not an absolute scale; it is relative to a set of standard solutions whose pH is established by international agreement. Pure water is said to be neutral. The pH for pure water at 25 °C (77 °F) is close to 7.0. Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are said to be basic or alkaline. pH measurements are important for medicine, biology, chemistry, food science, environmental science, oceanography and many other applications.
Report of the Working Party on pH, IUPAC Provisional Recommendation"]. 2001. http://www.iupac.org/reports/provisional/abstract01/rondinini_prs.pdf
. A proposal to revise the current IUPAC 1985 and ISO 31-8 definition of pH
Why is it important in a reef tank

Natural seawater has a pH between 8.0 and 8.25 and this is the range that the home aquarist should strive for. The concentration of carbon dioxide (CO2) has a direct influence on pH, via formation of a weak acid, carbonic acid, when carbon dioxide is dissolved in water. Carbon dioxide is absorbed by photosynthesis during the day (pH goes up), and liberated due to respiration at night (pH goes down.) These fluctuations are normal and should be of no concern unless they reach lower than 7.8 or higher than 8.5.

Alkalinity


Here we are concerned primarily with carbonate alkalinity and this concept is a very critical one for successful reef aquariums. Alkalinity is the measure of the buffering capacity of a liquid (in this case salt water) against addition of acid. Alkalinity is measured in meq/L (milliequivalents per liter) or dKH (degrees carbonate hardness). Reef systems should be maintained close to natural sea water levels or 2.9 meq/L or 8 dKH respectively. These levels are best achieved through the use of a balanced supplement like limewater, a two-part additive, or a calcium reactor. Alkalinity is one of the chemical parameters that must be tested regularly. There is also a close relationship between alkalinity, calcium, and pH in the aquarium
Calcium

(Ca)-a common ion found in sea water that is used by a variety of lifeforms including corals, mollusks, crustaceans, sponges and some algae in the production of their skeletal structures through a process called calcification. This is another parameter that must be tested regularly. Calcium readings are commonly expressed as ppm with natural seawater having a calcium concentration of between 400 and 450 ppm. As with Alkalinity, these levels are best achieved through the use of a balanced supplement like limewater, a two-part additive, or a calcium reactor.

Calcification

In aquaristics, this term almost always refers to the process that corals and calcareous algae use to extract calcium and carbonate alkalinity from seawater and turn it into their calcium carbonate structures. In a properly functioning system, available calcium ions and carbonate alkalinity are rapidly depleted by this process. Really what we are talking about here is the growth of your calcifying organisms. As a result of this growth, both calcium and alkalinity need to be supplemented on a regular basis
[FONT=&quot]REEFKEEPING 102 by RANDY DONOWITZ[/FONT]

What could affect your PH


The concentration of carbon dioxide (CO2) has a direct influence on pH, via formation of a weak acid, carbonic acid, when carbon dioxide is dissolved in water. Carbon dioxide is absorbed by photosynthesis during the day (pH goes up), and liberated due to respiration at night (pH goes down.) These fluctuations are normal and should be of no concern unless they reach lower than 7.8 or higher than 8.5.How to maintain your pH
pH levels can be controlled with buffers, but should not prove problematic with the appropriate use of any of the balanced calcium/alkalinity supplements.How to raise/Lower Your PH when needed
Maintaining good PH in a reef aquarium is one of the more common challenges. A low PH can negatively affect coral growth and lead to problem algae. There are a few easy workarounds to make sure your PH stays at or above 8.0
[FONT=&quot]Good Water Circulation[/FONT]
Good water movement in your setup is critical to keeping your PH high in your reef aquarium.
You also want to make sure that this flow causes surface agitation. Increased surface agitation will transfer the carbon dioxide out of the water and bring fresh oxygen into the tank.
[FONT=&quot]Proper Stocking Levels[/FONT]
Low PH in a reef aquarium can also be a sign of low oxygen levels. If so, increase the surface agitation and water flow levels. Fish are one of the biggest users of oxygen in your tank and having to many will have negative effects.
[FONT=&quot]The Right Substrate[/FONT]
One easy way to increase your reef tanks PH and hold it steady is to use aragonite sand or gravel in your tank. Aragonite will dissolve at lower PH levels and during this dissolving process it will release minerals and elements back into the tank that will in turn raise the PH. This is why it is critical you only use gravel or sand that is meant for reef tanks and not freshwater based material.

[FONT=&quot]Chemical Additives[/FONT]
If for whatever reason you just cannot raise PH in a reef tank or hold it steady you may have to turn to chemical additives designed to help you out. There are many two part additives on the market that will raise calcium and alkalinity and at the same time increase your tanks PH levels.
A great alternative is kalkwasser, set up to drip into your tank every few seconds, it will do a great job at maintaining calcium, alkalinity and PH. But like any chemical you add to your tan start slow and work your way up, and always test the results!
Testing pH

[FONT=&quot]pH can be measured by traditional titration test kits, dip and read test strips and most efficiently and accurately by a properly calibrated electronic meter.[/FONT]
 

Kanga

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Thanks Dallas, posted in the wiki
 
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dallasg

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thanks i will keep working on this, interesting and doing loads of research.

must i update here?
 

Kanga

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thanks i will keep working on this, interesting and doing loads of research.

must i update here?
If you like you can update here and I will add or PM me I will run you through the basic wiki editing:thumbup:
 
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