Water Quality

[Almondsaz]

If there is an existing thread...if someone can post the link that would be great. My question is my tank (45 gallon) is about 6 weeks old and the water quality has been good for the Amonia-Nitrites are 0 and my Nitrates are 10. Salt is 1.025 (has always been constant) and the PH is 7.92. My LFS checked the calcium becuase I was concerned that may be throwing off the PH and is was 480. They started me on Oceanic and he told me to use instant ocean becuase it would help in the H2O change to boost the PH and reduce the calcium. So my PH moved up a little to 8.00 will check the calcium this am...wanted the tank to churn for a few hours before checking.

Is there anything else I should be doing? I realize the PH should be about 8.2 and the Calcium should be more like 430.

Thanks in advance for the help!

David

 

[fsn77]

I wouldn't be too concerned about your calcium being 480 ppm in a 6 week old tank. It'll easily fall on its own once coralline algae starts taking off or any corals you might have really start consuming it without you needing to interfere.

Did the LFS test your alkalinity (KH)? Without knowing the KH of your tank, assuming that a calcium reading of 480 ppm is throwing off your pH is only a guess at best. There are other potential reasons for pH to be low:
http://www.reefkeeping.com/issues/2004-09/rhf/index.php

What time of day was the pH reading taken? Time of day can have a big influence on pH. Nonetheless, a pH of 7.9 is by no means anything to worry about. Yes, 8.1 -8.3 is pretty ideal, but it certainly is not essential. As long as you don't consistantly stay below 7.8 for any period of time, there is little to be concerned about.

 

[Almondsaz]

fsn77: thanks for your reply. When you say "for any period of time" would that be a month or a couple of weeks. The LFS did check that alkalinity and he said it was fine...didn't get the reading. The reading was taken about noon.

Had you ever heard of using the synthetic salt in a H2O change to impact PH and Calcium?

BTW your 90 gallon tank looks incredible.

 

[fsn77]

Almondsaz -- You're quite welcome... we're all here to help each other out. When I said "for any period of time," I was thinking more on the time scale of days to a week rather than weeks, a month, or longer. As pH gets lower, the calcification process used by corals and inverts slows, slowing their growth.

While changing salt brands can definitely effect water quality parameters, any single 10% - 20% water change will have a very small effect on your tank's parameters. Hypothetically, in a tank with a calcium level of 480 ppm, it would take a 10% water change with new sw that has 0 ppm calcium to lower the overall calcium level by 10%, or roughly near to 430 ppm. Granted, you definitely wouldn't want such a drastic change in such a short period of time, but that's just the point. Any change you'll experience in calcium levels is going to be one that's seen over the course of multiple water changes during the next few months. By then, other factors and processes will likely be influencing a drop in calcium without any need for changing to a salt mix that contains less calcium.

As for pH... that's not so cut and dry. If the reason for low pH is highly contributed to by the low pH of your current salt mix, then yes, changing salt mixes could help raise your pH. Again, this is something to be seen over time, as no single 10% - 20% water change is going to have that much of an effect on your overall system. Unfortunately, there's too many other potential factors effecting pH to definitely say that changing salt mixes will help raise your pH. In the end, it may help, however, it can just as easily not help at all.

FWIW, the pH of our reef tank stays right around 7.8 - 8.0 (depending on the time of day) and our calcium drifts around in the 350 - 420 ppm range and has for over a year and a half (ever since it was started). We still have what I would call good growth on our calcium consuming LPS corals, as well as all kinds of coralline algae. Our branching hammers and frogspawns branch regularly, as do our candy cane / trumpet corals.