help with ph and kh issues

[reefermike1]

alright a buddy of mines got a 10 gallon tank, lr and softie frags, and a clownfish. he started dosing kent nanoreef 2 part and his dkh is over 15, but his ph is real low at 7.6. i thought that the higher the dkh the higher the ph would be, but with the alk being that high does that cause ph to drop like that? im stumped and dont know what to tell him besides do waterchanges and stop dosing. but im looking for an answer as to why the ph is sow low.

thanks.

[luvmylo]

I'm bumfuzzled

[Fly Guy]

What kind of gas exchange does he have going on??

Is it a small room with lots of people, or is there a cover on the tank, or no sump and little to no surface agitation??

All of those things could result in a low ph regardless of other water parameters.

And the $100 question....how are you testing for ph??

[reefermike1]

used a salifert test, then double checked with a api for both alk and ph. the tank is pretty much sealed on top,got about an inch of open space on the back of the lid. but hes got a skilter cascade/skimmer thing, so i would think hes got somewhat of an o2 exchange. i told him to get rid of the lid, but thats what hes got his light sitting on.

[Fly Guy]

For kicks and giggles........do this

1. Test the tanks ph.
2. Take a cup of tankwater outside and violently stir the heck out of it.
3. Test the ph of the water in that cup

This little drill will at least eliminate gas exchange as part of the problem. Im willing to bet that with a cover on the tank that it will have at least some effect. Let us know how much or let us know Im wrong.

[reefermike1]

yea that is a good idea. he just came over with a baggy of water because he knows i have all the test kits and everything. so i let him borrow an api ph and kh kit, and told him to do the cup of water outside test. still those readings are scary lol. also gave him a 2.5 gallon jug of rodi water to do a wc with. feel like i did my good deed for the day lol.

[BoomerMn]

To expand on what Fly said it is irrelevant what the Alk/dKH is. Any CO2 input will drop the pH. The more CO2 the lower the drop. I might add the higher the Alk the higher the CO2 and the lower the pH the more CO2. NSW has about <0.50 mg/l at pH of 8.3 and Alk of 2.25 and you have about 5.5 mg / l CO2.

Low pH: Causes and Cures
http://reefkeeping.com/issues/2004-09/rhf/index.htm

[Fly Guy]

Originally Posted by BoomerMn

Low pH: Causes and Cures
http://reefkeeping.com/issues/2004-09/rhf/index.htm

Good reading there Boomer. Its late and it gave me a headache kinda...........but good stuff

[skeety]

Alk doesn't make the pH high or low. Alk is simply the buffering capacity (the ability) of the water to HOLD it's pH (make it more resistent to swings).

Here's some really good info on pH and Alk. I know it's a little long, but should read easy, and should still be helpful.

From the up-and-coming TRT Water Testing and Parameters FAQ:

[skeety]

pH:

What is it?
The pH value is a measurement of how acidic or base (opposite of acidic) the solution being tested is. Specifically, this is in comparison to pure water (H20), which is neutral, and has a pH of 7 (at ~25° C).

Why’s it Important?
This parameter is a little trickier to explain, without getting scientific, but let me try. pH is often misunderstood, but is actually an extremely important parameter in salt water tanks, as it affects a lot of different chemical reactions/factors in the tank, and ultimately every critter in it.

The most obvious affect is just the various critters ability to withstand a certain acidity or baseness. If the water is too acidic, or too base, it can downright burn certain critters. But that’s more at the extreme ends of the spectrum. In the middle though, slightly incorrect pH can still have profound affects on the system.

Again, without getting too scientific, the pH of the water affects chemical reactions that can take place in that water. Some of these chemical reactions are necessary in the tank, and some of them can be detrimental. The idea is to get the pH in the right range of the tank that promotes the good chemical reactions, and stops the bad ones. I’ll go into more detail about this later, but for now I’ll give a brief example of each.

A GOOD chemical reaction that we try to strive for in our tanks is Calcification. This is basically animals in your tank growing skeletons, by pulling calcium out of the water. We want our critters to grow, and if the pH is outside the optimal range, this can either become difficult, or downright impossible.

A BAD chemical reaction that can happen when outside the optimal range is that certain key metals/elements in the tank can become toxic, as they take on different chemical characteristics. Also, if the pH is low enough, DEcalcification can actually occur. Which basically means skeletal mass will start to actually dissolve in the water.

In general, think of pH as the tank’s ability to promote or stop various chemical reactions from taking place.

What Value should I Aim For?
It depends on what species of creature your trying to keep. Each critter has it’s own specific recommended pH range. So research the critters your planning on having in the tank, and keep that in mind as you read on.

Generally, anything from 7.9 to 8.4 is tolerable. Yet once again, the more important thing here is consistency. 8.1-8.3 is ideal, but many people have successful reefs that have an average pH of 7.9-8.0 or even a little lower.

In an established tank, from the time the lights come on until the lights shut off, the pH should rise gradually. Without getting too specific, this is due to photosynthesis. Algae and other photosynthetic organisms in the tank begin processing the light. As part of the photosynthesis process, CO2 (carbon dioxide) is consumed and oxygen is released into the water. This CO2 being consumed (reducing overall CO2 levels) causes the pH to rise.

When the lights go out, the pH will start to drop again, over the course of the night. The ideal range your pH should cover during this period is around ‘0.2’. So some good goal pH ranges are 8.0-8.2 or ideally 8.1-8.3.

Most beginners tend to see ranges from 7.9-8.1. The most common reason for this is poor circulation around the tank. As previously mentioned, CO2 decreases will cause the pH to rise. For the same reasons, CO2 increases will cause the pH to drop. If there isn’t good air circulation around the tank, the very act of you and your family’s breathing tends to cause higher than normal CO2 concentrations around the tank. This keeps the pH of the tank constantly lower than you may want. Switching your home air circulation’s fan from Auto to On (to constantly circulate the air in the house/apt) will work WONDERS if you have this problem. Also, opening doors and windows frequently (weather permitting) will correct this as well. If you can’t get around either of those, running some tubing from outside to your tank (most commonly through the skimmer’s air intake) will alleviate this as well.

What Do the Values mean?
As stated, pH is the measurement of how acidic or base a solution is, relative to pure water. pH values greater than 7 mean that the solution is more base than pure water, while pH values lower than 7 mean that it’s more acidic than water. The farther away from neutral (ph of 7) the value is, the more acidic or base that solution is.

It is important to note that the pH scale is logarithmic. This means that each whole number difference in pH represents in increase in the acidic/baseness by 10 times as much. (i.e. A solution with a pH of 9.0 is ten times more base than a solution with a pH of 8.0. Conversely, a solution with a pH of 4.0 is ten times more acidic than a solution with a pH of 5.0). Worse yet, that means a pH of 5.0 is 100 times more acidic that a solution with a pH of 7.0!

The main thing to note here is that as the pH gets farther away from your goal, the intensity of the pH increases very quickly. pH that’s just a little off (~0.2 units) isn’t that big of a deal. But a pH that’s off by 1 can mean a MAJOR difference.


The pH of some commonly known solutions:
Solution..................pH
Hydrochloric acid....-1.0
Vinegar................~2.9
Milk.......................6.5
PURE WATER...........7.0
Seawater.............7.7-8.3
Bleach..................12.5
Lye......................13.5

[skeety]

When Should I Test For It?
Most of the time, during normal tank operation, it’s not a single test result that’s valuable. Instead, what’s important is the range of the tank’s pH (over the course of the day) that’s important.

For the values to really give any insight into your tank’s condition, at least two test a day over a period of at least 2 or 3 days is needed. As stated above, pH should increase over the coarse of the day. So telling someone you tested your pH and it was 8.0 doesn’t really tell anyone very much. Was that the pH at the beginning of your photoperiod (the time your lights are on), in the middle of the day, or was it at the end? Without knowing that, and also having other test results you can’t really know the range the pH is.

So that said, pH should be tested in the moring, and in the evening right before the lights go off. Once you put critters in the tank, these tests really should be done daily or every other day until your confident in the consistency of your tank’s pH.

Any change in your tank’s lighting cycle should prompt another series of pH tests. Changes in ventilation, water chemistry, etc should also prompt pH testing.

pH really is a great indicator of the tank’s health. As you’ll learn later, when the pH is off, it can be the result of other parameters not being in line, or a symptom of potentially serious system problems.

Consider getting a pH probe that gives a constant readout of the tank’s pH. They are very accurate, and can save you lots of time instead of doing all these tests. They also help you figure out much quicker, when something’s not right with your tank. Knowing your tank’s pH values and the normal range your tank’s pH covers all the time is very valuable information and will be of considerable help in maintaining good tank health.

Any More Info?

pH as defined by Wikipedia
http://en.wikipedia.org/wiki/PH

A Comparison of pH Calibration Buffers (by Randy Holmes Farley)
http://www.reefkeeping.com/issues/2005-02/rhf/index.php

TRT Thread on how to control pH
http://thereeftank.com/forums/showthread.php?t=67560

[skeety]

Alkalinity:

What is it?
(Related to pH) Scientifically, alkalinity is a measure of the acid neutralizing capacity of a solution. I know…a bit wordy, right? But in regards to the marine aquarist, it’s simply the measure of the ability of your tank’s water to hold its current pH levels as well as a measure of the amount of calcium carbonate (used in the process of building skeletal mass).

The better your alkalinity value, the less likely you are to have pH swings. Alkalinity is also tightly relates to Calcium levels, but we’ll get into that later. In the marine hobby, this value is almost always measured in terms of Carbonate Hardness, or KH (not to be confused with general hardness GH, which is the value usually tested for in the Freshwater hobby).


Why’s it Important?
Alkalinity’s affect on the tank is a big one, but is rather indirect. As mentioned before, it’s mainly a measure of Calcium Carbonate, but without getting advanced, it’s also a measure of the tank’s ability to maintain its pH levels. So indirectly, if your alkalinity is off, then all the affects that pH has on the system come in to play. Bad alkalinity can allow rapidly shifting pH values which in turn will cause bad chemical reactions to take place in the tank.

Alkalinity is also very tightly related to calcification. Calcification really requires a scientific explanation to truly understand it, which is why I include a lot of links going into detail on this subject later on. But in staying with the goal of THIS article, I think it’s easiest to also think of it as the ability of the tank’s water to hold calcium as well as the critters abilities to utilize that calcium in the water column.

Once the tank’s water is super-saturated, Alkalinity and Calcium levels become inversely related. Raising alkalinity can cause Calcium levels to drop, and raising Calcium levels can cause alkalinity to drop. Let me explain this with an analogy.

Let’s say you have a normal sized shoebox and let’s say you an unlimited supply of red golf Balls and an unlimited supply of blue golf balls. You can only fit some finite number of golf balls in the shoe box, regardless of their color. Initially you can have a few red golf balls and way more blue ones. Then you could add lots of red ones to make the amount more even. You can keep adding various colored balls until eventually, the shoebox will be full. This is when the box has reached super-saturation (fancy word for, “it’s all full”!)

Take note that until the box fills up though, there is no correlation between the red and blue golf balls, meaning that adding a blue ball does not affect the number of red balls in the box. But once the box is full (super-saturated), in order to increase the number of blue balls in the box, you are going to have to remove a red ball.

This is what happens with Calcium and Alkalinity in your tank’s water column. The water can only hold so much dissolved stuff over all. Once it’s full, putting one in the water column can force the other out (precipitation).

At balanced super-saturated levels, corals can more easily pull the calcium they need from the water column, and as a result, can potentially grow faster. However, if the super-saturated line is crossed, precipitation can occur in the tank. This is a fine line to balance when trying to achieve optimal growth rates, and is only suggest for an advanced hobbyist. Achieving super-saturation is not necessary, and as long as Alkalinity and Calcium levels are in an acceptable range, growth will not be inhibited.

[skeety]

What Value should I Aim For?
Anything from 2.5-4 meq/L (7-11 dKh) is acceptable. Actually there is no exact target you should shoot for, until you get more advanced. For the most part, as long as you’re in that range, you are providing a good environment for your tank’s critters.

Higher alkalinity values than that range, and you can run into problems with precipitation. Basically, this means your water can not hold anymore calcium carbonate (main compound that an alkalinity value is measuring). So, as a result, excess calcium carbonate starts to solidify (much like when you put too much sugar in your iced tea). This excess will begin to accumulate on equipment, forming a crust or shell. This chemical reaction is easier in warmer areas, so it’s very common for things like heaters and pump impellers to get a build up on them. In extreme cases, you can even get what appears to be snow in the tank’s water column.

Lower values will cause instability in your tank’s pH level. This may result in constantly lower or higher pH readings. Or even worse, wild swings in the tank’s pH. This causes stress on all tank inhabitants leading to a slow demise, disease, and eventually death.

What Do the Values mean?
mEq/L - means milli-Equivalents per liter.
dKh - means degrees of Carbonate hardness, and is simply 2.8 times the mEq/L value.

Both of these are chemistry terms which to truly explain them would require chemical explanations that are more advanced than the purpose of this article. I’ve included links that go into more detail about each later in this section, but for now, let’s just think of them as units of measure for alkalinity.

When Should I Test For It?
Whenever your having problems with or trying to maintain your tank’s pH, Alkalinity, or Calcium levels.

If you are trying to keep calcifying corals (corals with a skeleton) and are trying to maintain good growth conditions, testing for alkalinity is a must.

Anytime you are dosing in any fashion in an attempt to affect pH, Alkalinity, Calcium, Magnesium, Strontium, etc levels, monitoring your Alkalinity levels is highly suggested. At least until you become familiar with it’s affect on your tank.

Any More Info?

Wikipedia definition of Alkalinity
http://en.wikipedia.org/wiki/Alkalinity

Wikipedia info on Equivelent (in relation to mEq/L)
http://en.wikipedia.org/wiki/Meq/l

A thread on TRT with some good beginner chemistry information as well as some good conversion formula’s.
http://thereeftank.com/forums/showthread.php?t=65197

A Simplified Guide to the Relationship Between Calcium, Alkalinity, Magnesium, and pH (by Randy Holmes-Farley)
http://www.reefkeeping.com/issues/2006-06/rhf/index.php

[BoomerMn]

Well, then lets go fo the whole 9 yards

A Simplified Guide to the Relationship Between Calcium, Alkalinity, Magnesium and pH
http://reefkeeping.com/issues/2006-06/rhf/index.php

When Do Calcium and Alkalinity Demand Not Exactly Balance?
http://reefkeeping.com/issues/2004-12/rhf/index.htm

Solving Calcium and Alkalinity Problems
http://www.advancedaquarist.com/issues/nov2002/chem.htm

How to Select a Calcium and Alkalinity Supplementation Scheme
http://www.advancedaquarist.com/issues/feb2003/chem.htm

Calcium and Alkalinity Balance Issues
http://reefkeeping.com/issues/2002-0...ure/index.htm0

Calcium Carbonate as a Supplement (Aragamight; Liquid Reactor)
http://www.advancedaquarist.com/iss...ly2002/chem.htm

The Relationship Between Alkalinity and pH.
http://www.advancedaquarist.com/issues/may2002/chem.htm

The Chemical & Biochemical Mechanisms of Calcification in Corals
http://www.advancedaquarist.com/issues/apr2002/chem.htm

Low pH: Causes and Cures
http://reefkeeping.com/issues/2004-09/rhf/index.htm

High pH: Causes and Cures
http://reefkeeping.com/issues/2005-03/rhf/index.htm


What is that Precipitate in My Reef Aquarium?
http://reefkeeping.com/issues/2005-07/rhf/index.htm

The Units of Measure of Reefkeeping
http://reefkeeping.com/issues/2005-08/rhf/index.php

[Marcalo]

circuits overload system malfunction powering down

thats alot of reading but good info on both parts i'll have to ue that on my next tank