PH and Alkalinity I don't get it

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BryanB

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Ok so PH and alkalinity are a direct link to one another. So if I dose for alk my ph goes up as well I am told, but if I have a calcium reactor it will force my ph down while making alk and calcium. What am I missing.
 
The reason why calcium reactors lower the ph is because you're using co2 to lower the ph within the reactor to dissolve the calcium; therefore the effluent leaving the reactor has a substantially lower ph and consequently lowers the systems ph. The best way to counteract this is to top off with limewater, which has a very high ph.
 
Lime water you say? Is there a table of concentration amount to use. I think that makes sense. Basically where do I get it and how much to use?
 
Knock knock Randy.....are you home? We need a interpretation on alk and ph....alk is a measurement and not a element in your water...stable ph is based upon your ability to find the "sweet" spot in your tank based on alk...I know this is confusing...I bet Randy can explain it a little better to you.....
 
Calcium reactor and Kalk reactor..... Works perfect for my system. Top off goes through kalk reactor. Bio pellets in pic have been removed.

ImageUploadedByREEF2REEF1425443339.414399.jpg
 
Lime water you say? Is there a table of concentration amount to use. I think that makes sense. Basically where do I get it and how much to use?

What type of corals do you have and how full is your tank? The reason I ask is because if you have a young reef, not a lot of stony corals, or just a lot of small stony frags a calcium reactor may be an unnecessary expense right now. Typically your cal and alk dosing progresses from limewater, to limewater and 2 part, to limewater and a calcium reactor as your reef develops and grows from small frags to large colonies and consequently the consumption of cal increases along with the expense of supplementing.

For example, my 90 gallon reef is packed with stony corals and I've been able to maintain cal and alk with a still 20 gallon limewater ATO for over a year. I started out with 1 teaspoon per gallon to 2 teaspoons per gallon, now I add vinegar to increase the amount of lime I can add and I would start dosing 2 part in the near future, however, I'm in the process of upgrading to a 300 gallon system so I will be restarting my dosing scheme.

What Your Grandmother Never Told You About Lime by Randy Holmes-Farley - Reefkeeping.com - limewater

Chemistry And The Aquarium: How To Select A Calcium And Alkalinity Supplementation Scheme ? Advanced Aquarist | Aquarist Magazine and Blog - selecting a calcium and alkalinity scheme
 
What type of corals do you have and how full is your tank? The reason I ask is because if you have a young reef, not a lot of stony corals, or just a lot of small stony frags a calcium reactor may be an unnecessary expense right now. Typically your cal and alk dosing progresses from limewater, to limewater and 2 part, to limewater and a calcium reactor as your reef develops and grows from small frags to large colonies and consequently the consumption of cal increases along with the expense of dosing
Well I happened to trade parts for parts and wound up with a 90% complete georeef 618 which is rated at 300 gallons and my tank being 200 I ordered up the pump, probe and regulator. I have bean dosing Red Sea three part foundation. My corals are as follows and are at the trying to be colony size.
Corals
1.Hollywood stunner
2.Dragon soul favia
3.Rainbow montipora (Jason fox)
4.Ora pink and green damicornis ?
5.Grape coral (super green)
6.Green slimer x2
7.Tri color porcillopora
8.Burning povona (Steve tyree)
9.Bright green mouthed candy cane 8 heads
10.Orange and green blasto 3 heads
11.Lime light stylophora (Jason fox)
12.Red and white acan 6 heads
13.Ora neon green birds nest
14.Meteor shower
15.Duncan 2 heads
16.Orange stylophora (Steve tyree )
17.Exenia
18.Sour apple cap
19.Orange cap
20.Branching frog spawn 2 heads
21.Purple and green garf Bosnia
22.Blue berry acro
23.Ora green stylophora
24.Super fuzzy teal acro
25.Orange plate w/ green polyps
26.sympodium polyps
27. Maze brain
29. Orange acan 8 heads
30. Green long polyp orange mouth plate
31. Supper orange crush echinata
32. Australian bi color wall hammer
33. Elegance coral peach orange green
34. Australian rainbow torch
Assorted zoas, palys and mushrooms
 
This is a preemptive strike the final parts for my Ca reactor will be here today and I have read about the low PH problems so I want to be prepared.

What is your normal pH range? pH isn't a useful number to chase as long as it's between 7.9-8.4 or so. It's hard to be below that range at reef alkalinity levels, so I've found that if that's the case it's elevated CO2. Like reef life mentioned, running the effluent into the skimmer area will gas off a lot of that CO2. Likewise, you could run your skimmer air intake outside for air with less CO2.
 
Ok. Yeah, set up the reactor and add kalkwasser to your top off. You can buy it online or from your lfs. Or you can buy Mrs. Wages Pickling lime from your local grocery, same thing. Just add the correct amount of kalk to the volume of water (maximum 2 teaspoons per gallon, unless you add vinegar) stir it up and let it settle and only dose the clear limewater.
 
Ok so PH and alkalinity are a direct link to one another. So if I dose for alk my ph goes up as well I am told, but if I have a calcium reactor it will force my ph down while making alk and calcium. What am I missing.

They are related, but an alk supplement can drop pH a bit (baking soda), drop it a lot (a reactor ), or boost it a lot (sodium carbonate) or boost it even more (limewater), depending on how much CO2 comes in with it.
 
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The important bit boils down to this. Your alk is fixed in that it is whatever you want to run you tank at. You want natural levels - 7 dkh. Elevated levels - say 10 dkh. But alk only has a minor effect on pH. Raised alk slightly increases pH.

More powerful effects on pH are caused by CO2. Lots of CO2 in the water means low pH, low CO2 in the water means high pH. If you add a calcium reactor and lots of CO2 gets into your tank the pH will be low. If you have your tank in a well sealed room with lots of people in it for many hours, the CO2 will build up in the air and get into the tank and you have low pH. If you have lots of life like fish in your tank they will also add CO2 and lower pH.

For your situation to prevent the CO2 from the calcium reactor getting into the tank you need to do something like very well aerate the reactor effluent (the water leaving the reactor going to the DT). Bubbling air through it for instance. The more air and bubbles the more you will scrub CO2 from it. IF thats not enough then limewater can directly absorb CO2 from the tank (but it rasies alk and calcium).
 
They are related, but an alk supplement can drop pH a bit (baking soda), drop it a lot (a reactor ), or boost it a lot (sodium carbonate) or boost it even more (limewater), depending on how much CO2 comes in with it.

...and in all scenarios, pH in the tank gravitates back to the level dictated by ambient co2 levels in the room that houses the tank. Usually with a quickness if there is decent aeration. :)
 
...and in all scenarios, pH in the tank gravitates back to the level dictated by ambient co2 levels in the room that houses the tank. Usually with a quickness if there is decent aeration. :)

Agreed. I always have a ph of around 7.8 because my house is sealed. But with all of the other numbers in check, I don't worry about it.
 

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