crushed Coral!
- Thread starter kimlynn
- Start date
He doesnt have to get crushed coral. If anything the crushed coral will help raise the ph. That is why it used so often in saltwater setups, as there ph is 8.4 or so.
The most common substrate to use is either sand, top soil (if your going planted) or normal gravel.
The most common substrate to use is either sand, top soil (if your going planted) or normal gravel.
Crushed coral will raise pH.
CaCO3 --> Ca+ (CO3)2-
H2O <--> H+ + OH-
H+ + (CO3)2- <--> HCO3-
H+ + H(CO3)- <--> H2CO3
Carbonate ion is unstable and reacts quickly to form a more stable species. As the reaction proceeds, H+ is reduced in solution. As a result, pH will decrease.
You shouldn't mess with pH unless you're a breeder. Every time you do your water change, you need to make sure that your new water is the same altered pH.
CaCO3 --> Ca+ (CO3)2-
H2O <--> H+ + OH-
H+ + (CO3)2- <--> HCO3-
H+ + H(CO3)- <--> H2CO3
Carbonate ion is unstable and reacts quickly to form a more stable species. As the reaction proceeds, H+ is reduced in solution. As a result, pH will decrease.
You shouldn't mess with pH unless you're a breeder. Every time you do your water change, you need to make sure that your new water is the same altered pH.
A good choice would be to use topsoil first and then put down some fine sand such as pool filter sand, or gravel. The top soil will have alot of nutrients the plants will use.
You might want to rethink that statement. kH = alkalinity. Alkalinity= resistance to pH change. Increasing alkalinity won't alter how much the pH drops when CO2 is introduced?
Correct. Check it out on the pH/KH/CO2 tables. It changes the starting and end points, but not the diistance between them.
The problem is an oversimplistic understanding of alkalinity.
For example, use the table here: http://www.thekrib.com/Plants/CO2/kh-ph-co2-chart.html
Consider adding 15ppm CO2, from 15ppm to 30ppm.
At KH 4, that would move the pH from 6.9 to 6.6 - a change of 0.3 points on the pH scale
At KH 8, that would move the pH from 7.2 to 6.9 - a change of 0.3 points on the pH scale - i.e. the same.
It's a common misconception.
The problem is an oversimplistic understanding of alkalinity.
For example, use the table here: http://www.thekrib.com/Plants/CO2/kh-ph-co2-chart.html
Consider adding 15ppm CO2, from 15ppm to 30ppm.
At KH 4, that would move the pH from 6.9 to 6.6 - a change of 0.3 points on the pH scale
At KH 8, that would move the pH from 7.2 to 6.9 - a change of 0.3 points on the pH scale - i.e. the same.
It's a common misconception.
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