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Discussion Starter · #1 ·
newby here, i have a few questions...

what is Alkalinity and the purpose for testing it?

and what does it mean if my PH level drops, i just tested and it shows 7.8 when just a few days ago it was at 8.2, what should i do to correct this?

thankyou.
 

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you would have to ask the hard questions... I barely understand it myself.

Alk is essentialy the buffering capacity of the water (aka its ability to maintain a consistant PH) if your PH is swinging then you need to look at you alk level. you may need to use a buffer.

where is tom when you need him?
someone else will come along and explain it in better detail... this is one detail i never explain, i just watch my levels and keep them where they need to be.
 

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Discussion Starter · #3 ·
what kinda buffers are out there, i have used a powder type but never really saw any difference from it in the past.

should i do a 10% water change or do the buffer or both???
 

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Welcome to TRT. This is a Great Place for those questions. Everybody here is very helpful and there is lots of knowledege that is shared.

Regarding your Ph issues what else is up with your tank? how big, when was the last water change, how old is the tank, what kind of things are in the tank, what are the other paramiters such as ALK, Calcium, Phosphate, Nitrate, Amonina,

Ph and ALK go hand in hand (sort of) as per Aquiarium Corals book by Eric Borneman Alk reflects the waters capablity for the ph to resist changes the higher the alkalinty the more stable the PH. The natural range for sea water is from 7-12 DKH or 3.2-4.5 meq/L

As for what to add to the tank is up to you and what you keep in the tank. I use Kent Superbuffer powder as per the directions plus Kent calcium part A&B. let's hear about the tank peramiters before anything gets added.
 

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Welcome to TRT. Not sure on alk but ph changes due to time of day you test. Your morning reading will be different than your mid day. One of the pros can explain further. It may not be anything to worry about.
 

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blacksunshine said:
what kinda buffers are out there, i have used a powder type but never really saw any difference from it in the past.

should i do a 10% water change or do the buffer or both???
Both.

Since your question is about alkalinity I will briefly mention why the water change, and then go on to explain alk, ph, etc.

Water changes are important for many reasons. One of the important things to understand about a reef tank, is that the level of nutrients (nitrogen and phosphorus mostly) need to be kept very low. So, you need good import/export husbandry. In otherwords, the water changes help to clear out nutrients, especially if you siphon the detritus off the bottom. This is part of the export equation which also includes protein skimming, and refugiums for the most part. Water changes also help to replace trace elements, and magnesium among other things, which may be lost to biotic or abiotic precipitation.

Now why is alk important. First of all, alkalinity is simply the buffering capacity of the water. In other words how much acid can be added before the pH is significantly changed. Without getting into the details (I will let Tom do that) alkalinity is comprised of several different anions, but we generally focus on bicarbonate and carbonate. This is because not only is bicarbonate and carbonate a large part of the alkalinity of the water, but it is also used by corals and calcareous algae as part of their skeletons. Simply put you want high levels of alkalinity, mainly from carbonate bicarbonate, and you need a method of maintaining these high levels. Initially the levels are high in most salt mixes, but the alkalinity drops in the tank over time from precipitation (either biotically by corals as mentioned above, or by precipitating out of the water with calcium) or by reacting with an acid. In order to maintain high alkalinity levels you will need to either use a two part buffer (this includes kalkwasser) or you need to do water changes. Whether or not water changes are enough depends on details of your tank that you have not provided. How big is your tank, what is the salinity, what is the temperature, pH, what critters do you have in the tank, how much LR, what is your filtration method, etc.

pH is a measure of the hydrogen ion concentration in the tank. It is related to alkalinity, if your alkalinity is low your pH will tend to be low also, but it is possible to have a low pH with high alkalinity. pH fluctuates throughout the day. During the daytime/lights on period, photosynthesis draws CO2 out of the water. pH is mostly related to CO2, higher CO2 levels means lower pH, lower CO2 higher pH. As the CO2 concentration in the water goes down from photosynthesis, the pH rises. So the lowest pH is just before the lights go on, and the highest is just after the lights go out. So when you give us the pH the relation to the photoperiod is important.

You want good testing methods, essentially a calibrated pH probe, salifert alkalinity, calcium, and magnesium test kits.
 

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welcome... you will get some great answers here. and if you have more questions, ask away. im not to good on this subject though, so the pros will step in.
 

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Discussion Starter · #10 ·
wow, i wasnt expecting this many replies!

first off thankyou all for the responses...

Regarding your Ph issues what else is up with your tank? how big, when was the last water change, how old is the tank, what kind of things are in the tank, what are the other paramiters such as ALK, Calcium, Phosphate, Nitrate, Amonina,
current tank/setup: 12g NC dx, topless, stock pump, hydorflow, 130w jbj fixture on top, fan across the water 24/7, water temp between 77-80, about 10lbs LS, 10lbs LR, tank inhabitants: green, orange, blue zoas; gsp, red, green, purple shrooms, hawaiian feather duster, 2 blue leg hermits, 2 turbo snails, 1 bumble bee snail, 3 small nasarius snails. last water change was 4 days ago, it was a gallon. tank was started first of april. i did wait a full month before i started adding things, and made sure nitrates/nitrites were at a zero. i need an ALK test kit, but here at the parameters otherwise... Nitrite: 0, PH: 7.8 (lights on for about 6hrs), Nitrate: 1.5, Ammonia: 0, Calcium: 415, salinity: 0.024

7-12 DKH or 3.2-4.5 meq/L
what is DKH and MEQ?

DRSYME: where would i get a phprobe? who sells them?
 

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drsyme's explanation was pretty good so I won't add anything to that.

DKH and meq/L are just the units used to measure alkalinity. Some test kits use DKH and some use meq/L. I believe 1meq/L=2.8DKH but that is just from memory so don't hold me to it.
 

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Tank sound great nothing is out of wack. there are no fish so your bio load is low to non existant. I wil let somebody else weigh in on the water changes.

DKH and MEQ/L are the common measurements for Alkilinity

One more thing where are the pics??
 

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Discussion Starter · #16 ·
im working on a camera, if those water parameters sound ok........ why are my GSP not opening? everything else is doing just fine.
 

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hmm, sounds interresting; hopefully someone here might have an answer for you. "BUMP"
 

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i belive once you have the PH back to were it should be the GSP will open up fully. ( word of warmning GSP are very good of growing and spreading kinda fast. if you have the rock they are one close to another "empty" rock they will spread to that and any other rock close by.)
 
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