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Question for ceg4048

No worries then. 98% of people here dont know this truth, thats all. I thought since its a site based on quite good knowledge that it would be a good fact to stablish.

About people who just cant argue science and who get personal if removed from their confort zone..... we can just forget about them all.
 
I dont want to throw more wood to the fire but this are cegs words from Sachas post:

http://www.ukaps.org/forum/threads/my-ph-profile.31565/page-4

"The rest of the advice goes like this:
"If you have a low KH then you need a much larger drop by lights on"
"If yuo have very high KH then you may not need a 1 unit drop. A 0.5 unit (or so) drop may suffice"

Few people in UK have low KH, so generally a 1 unit drop is the target.

If your fish are fine then you can improve the injection rate, but be there to monitor.

Cheers,"

So it seems to spread the myth even further.
 
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I am reminded of the sounds of the locust's I hear while night fishing on the river/lakes .
Although they have nothing of discernible importance to say far as I can tell,they none the less continue with their chatter as is their nature to do so.
I suspect they enjoy hearing the sound they make.
 
roadmaster said:
I am reminded of the sounds of the locust's I hear while night fishing on the river/lakes .
Although they have nothing of discernible importance to say far as I can tell,they none the less continue with their chatter as is their nature to do so.
I suspect they enjoy hearing the sound they make.
Click to expand...

Ignorance is up to each one to have for their own. Me, I like knowing. Once again its not about me.
 
Jose said:
Ignorance is up to each one to have for their own. Me, I like knowing. Once again its not about me.
Click to expand...

Well, I would not go so far as to call the insect's ignorant,just annoying.
 
Jose both you and that guy who says you are 100% are going around in circles. First you were saying that a 1pH drop in any KH equals around 30ppm CO2 then that other chap says that with a lower KH 30ppm of CO2 will cause a larger drop in ph (the 1-1.5 you have mentioned) and he also says that with a higher KH with 30ppm CO2 you will get a smaller drop in pH of around 0.5.

You agreed with this statement because he said you are 100% correct but it kind of contradicts yours.

Your tap water CO2 has no importance because it will only be a factor on the day of your water change so lets ignore it w.r.t the calculations

Ill just try to summarise this simply :

If you have a low KH and add 30ppm CO2 you will see a large drop in pH
If you have a high KH and add 30ppm CO2 you will see a smaller drop in pH

The key point here is that you are adding 30ppm of CO2 in both cases and reaching the CO2 levels that you need in your planted tank. you arent adding CO2 to lower the pH of your tank or to neutralize the KH carbonates. So no matter whether you get a small or large swing in pH you are still adding enough CO2 for your plants.

The KH and pH charts are only to make it convenient for you to figure out your CO2 levels in terms of ppm
 
Mortis said:
The KH and pH charts are only to make it convenient for you to figure out your CO2 levels in terms of ppm
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and they cant do that with any accuracy according to those charts and my water report I'm pumping 200 ppm of co2 into my tank but they are a good starting point
 
When CO2 dissolves, being a weak acid, the amount of H+ released is enough to drop the Ph but not enough HCO3- are released to affect the Kh itself(you may need to inject a thousand more times of CO2 to actually affect the Kh). That's why alkalinity doesn't matter when dissolving CO2 and also your fish aren't affected by the Ph drop as it' doesn't affect the KH. Well at least that's how I understand it.
 
The 1ph drop is a generalised statement relating to near neutral Ph with a supposed KH that relates to that Ph. Aiming for a 1ph drop is a good starting point for most people. To explain in more detail the poster may as well say nothing other than 'Here's a linky to a ph/KH chart'.

This is the reason we use drop checkers with an known 4KH solution within it. We know it is not contaminated by anything else that would affect the result being that 30ppm will change the colour of the 4KH solution (with its bromo blue reagent) from blue to green.

You can do the same with the ph/KH charts BUT you then need to know the ph and KH of your water sample(s) and you are also allowing contaminants that are in the tank sample(s) to potentially affect the result.

So there is no contradiction really. It is a generalised statement which will be close enough for most people and at worst a good starting point versus going into detail about the relationship between KH and PH.

At the end of the day (IMO which can be a bit sharp) is that if someone couldn't be bothered to (re)search themselves about the PH/KH relationship then a statement of 'Aim for a 1ph drop' is probably the best answer for them.
 
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