Ph and Alkalinity low

Caleb423 · Aug 30, 2016

Hey everybody, just did a water test and my ph and alkalinity is low. Ph is 7.8 and alk is at 6 dkh. I have never had any trouble maintaining ph or alkalinity. During the past few weeks my water test have been showing my ph, alkalinity, and calcium dropping. I will post the results below. What should a do to raise ph and alkalinity? Should I just add buffer?

8-13-16

Ph- 8.4
Alkalinity-9*dkh
Calcium- 320ppm

8-28-16

Ph- 8.0
Alkalinity- 7*dkh
Calcium- 280ppm

8-30-16

Ph- 7.8
Alkalinity- 6* dkh
Calcium-280ppm

I did a 30% water change after testing water on 8-28-16.

Why are these levels dropping so rapidly?

Also this is a 29g with fish, live rock, and soft corals.

Burcu · Aug 31, 2016

Hi

Alkalinity acts like a buffer, which protects the stability of PH. KH should be protected between 7-10 according to your coral variety, PH 8 or higher. According to PH-KH decreasing, the CO2 consantration increases. So you can use KH buffer first to raise KH (to keep PH stability) and then you can raise Oxygen to raise PH. Making more wave at the water surface, or using an air pump at sump is some ways. Corals make photosynthesis with light and give oxygen to water. This is the reason that PH reaches the highest point near the lightning off time. You can also extend the time of your lightning. (But not more than 9 hours)

Calsium is being used by corals as long as you keep the ionic balance stable. When ionic balance is out of order (Or Magnesium levels are low), calsium stays stable, you cant raise it. (The chemistry is much more complicated that I cant stil understand

) So when you get the KH-PH balance again, (and if Mg is ok) probably your calsium level will start to decrease very quickly. It is very low currently (should be 400-450 ppm), so you need to raise it after you get the ionic balance back. (raise not more than 30-40 ppm a day)