Originally Posted by bharada
Ususally having a 3dKH level is sufficient to prevent a catastophic pH crash due to excess CO2. Why do you need it higher? If the pH is fluctuating then you need to find the cause of this. Also, if your wood (or anything else in your tank) is affecting your pH then any CO2 readings based on pH/KH will be inaccurate.
Also, are your pH fluctuations occuring during the same time period on different days? I ask because pH level will fluctuate during the day as the plants consume the carbon during photosynthesis, which will cause the pH to rise. At night, as the plant release CO2 back into the water your pH will fall. You also list CO2 injection by DIY generators which can also cause the pH to fluctuate due to inconsistant CO2 production.
Finally, to answer your question, crushed coral can be used to increase KH and GH, but in your particular situation I don't believe it is the solution to your problem.
If kH is to be higher, I will probaly get a more stable pH, or at least a smaller range of fluctuation limits.
I usu take those tests when my tank is in daylight operating. I know abt photosysthesis system.
The root cause I would suspect most of the time, is the DIY CO2 that caused the fluctuation. Every 1 or 2 day , i need to regulate the control valve. Its diffucult to have consistent CO2 throughout 1 week o so. Have you heard of DIY Yeast mitures, CO2 generator that burst? Thats why control is a must for DIY.
Im not sure how consistent is CO2 using a pressured tank, with those selonoid and needle valves, i have never try it.
I would treat DIY CO2 as a variable, the strategy here is to keep FIX constant of high 5dkH, in order to maintain pH with a smaller fluctuation limits. I usually, add 1.5 teasp of Bicarbonate of soda, (not sodium bicarbonate i mention earlier, its typo) per 100 litre every weekly water change. I have trying adding more, yet it maintain at 3.5 highest.
However, if i add crash coral in the canister filter to keep high kH, I would have reduce 1 maintainence. Well, adding Bicarbonate of soda 52 times throughout a year, is not an ideal solution either......
Do adivse if this method of maintaining and increasing kH n pH is feasible. If yes, my other concern is CO2 lost, due to chemically react with crash corals. I inject CO2 direct into tank using a reactor. Any chemist here that can relate crash corals and CO2?