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Hello Aquapons, My GH is off the scale. My PH is holding at 7.6 to 7.8 Cant seem to move it lower with acid. Using Nylons with peat to try and help. Any Ideas. The KH is at 125ppm as well.

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it's the carbon filters that don't remove the carbonates.

 

Then again, there are different levels of RO filtration I believe and I don't know to much of the details about them other than Nate says he has used them to deal with his hard well water where he is and since they don't get much rain he has little other choice if he want to avoid the hard water issues.

Great explanation, Rupert.  Explains why the pH of my new systems is so high (above 8). Our water comes from wells along the Platte River, near which are huge deposits of calcium carbonate with mines running miles undergroud.  Is there anyway to naturally accelerate the "exhaustion" of this buffer?

feed the fish more.

No fish yet.  Just started the system last Saturday.  It's too early to add fish, right?  It's my novice understanding that I need to get the biofilter up and running first.  Correct?

 

Ok if you don't have the bio-filter started yet, you can use acid to adjust the pH of your water and deal with some of the buffer.

Muratic acid works.  Get the pH down somewhere between 7-8 and then start your fishless cycling.

Once you are fishlessly cycled you may find you need a bit of buffering back.

TC... here's where I am a bit unclear.  I read your blog on fishless cycling. Here's what I think I need to do: 

• add ammonia/hummonia to the system (which is about 130 gals all totaled) to bring ppm to 1-2 range

• adjust ammonia dosing until start to see measurable nitrate and nitrite levels in the 1-2 ppm range as well

 

Do you advise 'innoculating' the system with river rock/sand. I can get some from the Platte. Ag nitrites should be at minimum this time of year.

 

 

The bacteria will show up on it's own so "innoculating" is not necessary.  Now If you know some one near by with an aquaponics system that would give or sell you a bag full of mature wet media it might help to bury that in your system or maybe if you know some one with a healthy non chemically treated aquarium you could use the filter squeezings if you like to innolculate your system.

 

I'm not sure how effective rocks from the river will really be for you but if you are setting this up in a relatively "sterile" indoor environment, maybe it would be worth a few hand fulls of rocks from a natural environment (I would avoid sand though.)

 

Yea about the cycling.  You want to dose up to between 1-2 ppm and avoid dosing that puts the ammonia over 4 ppm since you want to keep that on the scale.  When the nitrite spikes you can ease off dosing till you see that fall.  Then you will dose between 1-2 ppm and check both ammonia and nitrite the next day, when you get to the point that the ammonia and nitrite are both 0 24 hours after a dose, then you are fishlessly cycled up.  You can keep the bio-filter alive by dosing until a day or two before you will get fish.  You want to let the ammonia and nitrite fall to 0 before putting new fish in the system.  Keep an eye on your pH through all this since there is a good chance the pH will drop about the time you are cycled up.  You want to keep the pH up in the measurable range.

That's exactly the information I was looking for.  Asking Kip Edmonds to 'borrow' some of his bugs.  Thanks!

TC.... quick question:  Which do I want to address first?   pH or ammonia dosing?   Or can you do them at the same time?

 



TCLynx said:

The bacteria will show up on it's own so "innoculating" is not necessary.  Now If you know some one near by with an aquaponics system that would give or sell you a bag full of mature wet media it might help to bury that in your system or maybe if you know some one with a healthy non chemically treated aquarium you could use the filter squeezings if you like to innolculate your system.

 

I'm not sure how effective rocks from the river will really be for you but if you are setting this up in a relatively "sterile" indoor environment, maybe it would be worth a few hand fulls of rocks from a natural environment (I would avoid sand though.)

 

Yea about the cycling.  You want to dose up to between 1-2 ppm and avoid dosing that puts the ammonia over 4 ppm since you want to keep that on the scale.  When the nitrite spikes you can ease off dosing till you see that fall.  Then you will dose between 1-2 ppm and check both ammonia and nitrite the next day, when you get to the point that the ammonia and nitrite are both 0 24 hours after a dose, then you are fishlessly cycled up.  You can keep the bio-filter alive by dosing until a day or two before you will get fish.  You want to let the ammonia and nitrite fall to 0 before putting new fish in the system.  Keep an eye on your pH through all this since there is a good chance the pH will drop about the time you are cycled up.  You want to keep the pH up in the measurable range.

What is your pH anyway?

You can probably go ahead and start adjusting pH and go ahead and do your first ammonia dose at the same time.  Since you haven't even started cycling yet it isn't like there is anything to really hurt in your system yet if you mess up.

 

In the future once your system has bacteria, fish and plants, I would recommend adjusting pH of your top up water before you add it to your system.  Hopefully you won't need to do that constantly but if your water is really hard you might want to look into ways to collect rain water to supplement and avoid too much calcium carbonate in your system.

Rupert.....I realize this is an old post but hopefully you or someone else will give me a little advice related to this.  We have well water with ph of 7.6 and about 400 sq feet of gravel bed that although it did not show carbonates with vinegar test, it did show it when tested with muriatic acid.  After water cycles thru bed, ph goes up to 8.0 now which is better than a few months back at 8.6.  I have added gallons of muriatic acid, ph down over the last few months  which lowers into mid 7's but then creeps back up so I think I may need to just get the RO system.  We are going on about 6 months now after cycling.  Nitrates, Nitrites all good levels but plants could be better.  Does it make sense to run any water we put into system thru the RO and will that lower the PH  even though once it goes thru gravel bed, it will go up again ?  I am thinking it will go in more like around 7 rather than 7.6 and come out thru the gravel around 7.6 if the current ratio holds true .  

RupertofOZ said:

The above will lower your carbonate hardness (kH)... not necessarily your general hardness (gH)... which is more a measure of the combined magnesium, calcium and other metalic ions present in your water... what's often referred to as "hard water"...

 

A general technical explaination...

 

There are two types of water hardness: general hardness (GH) and carbonate hardness (KH).  A third term commonly used is total hardness which is a combination of GH and KH. 

 

Since it is important to know both the GH and KH, the use of total hardness can bemisleading and should be avoided.

GENERAL HARDNESS 

General hardness is primarily the measure of calcium (Ca++) and magnesium (Mg++) ions in the water.  Other ions can contribute to GH but their effects are usually insignificant and the other ions are difficult to measure.  GH will not directly affect pH although "hard" water is generally alkaline due to some interaction of GH and KH.

GH is commonly expressed in parts per million (ppm) of calcium carbonate (CaCO3), degrees hardness (dH) or, more properly, the molar concentration of CaCO3.  One German degree hardness (dH) is 10 mg of calcium oxide (CaO) per liter.  In the U.S., hardness is usually measured in ppm of CaCO3.  A German dH is 17.8 ppm CaCO3.  A molar concentration of 1 milliequivalent per liter (mEq/l) = 2.8 dH = 50 ppm. 

 

Note that most test kits give the hardness in units of CaCO3; this means the hardness is equivalent to that much CaCO3 in water but does not mean it actually came from CaCO3. 

 

Water hardness follows these guidelines:

      0 -  4 dH,    0 -   70 ppm : very soft
      4 -  8 dH,   70 -  140 ppm : soft
      8 - 12 dH,  140 -  210 ppm : medium hard
     12 - 18 dH,  210 -  320 ppm : fairly hard
     18 - 30 dH,  320 -  530 ppm : hard
     higher : liquid rock (Lake Malawi and Los Angeles, CA)

General hardness is the more important of the two in biological processes.  When a fish or plant is said to prefer "hard" or "soft" water, this is referring to GH.  Incorrect GH will affect the transfer of nutrients (trace elements) and waste products through cell membranes and in AP systems...

 

CARBONATE HARDNESS

Carbonate hardness (KH) is the measure of bicarbonate (HCO3-) and carbonate (CO3--) ions in the water.  In freshwater aquariums or aquaponic systems of neutral pH, bicarbonate ionsv often predominate.

 

Alkalinity is the measure of the total acid binding capacity (all the anions which can bind with free H+) but is comprised mostly of carbonate hardness in freshwater systems. 

 

Thus, in practical freshwater usage, the terms carboante hardness, acid binding, acid buffering capacity and alkalinity are used interchangeably.  In an aquarium, or aquaponis system, KH acts as a chemical buffering agent, helping to stabilize pH.  KH is generaly referred to in degrees hardness and is expressed in CaCO3 equivalents just like GH.

In simple terms, pH is determined by the negative log of the concentration of free hydrogen ions (H+) in the water.  If you add a strong acid such as hydrochloric, or nitric acid to water, it completely dissociates into hydrogen ions (H+) and its "conjugate base" or "salt".

 

The hydrogen ions freed in the reaction then increase the concentration of hydrogen ions and reduce the pH.  Since nitric acid is the end product of the nitrogen cycle, this explains why aquarium pH tends to decrease and nitrates tend to increase over time.

When the aquarium has some carbonate buffering in it, the bicarbonate ions will combine with the excess hydrogen ions to form carbonic acid (H2CO3) which then slowly breaks down into CO2 and water. 

 

Since the excess hydrogen ions are used in the reaction, the pH does not change very much.  Over time, as the carbonate ions are used up, the buffering capacity will drop and larger pH changes will be noted.

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