55 gallon SPS reef- new additions (12/18/14)

If you recall I moved everything into a new apartment back in December, so everything was stirred up and re-added then. My growth and color exploded soon after. Some of the rock has been in the tank for 2 or 3 years now, others were in there for a few months.

I suppose I'll get started on those water changes. You're right, I have nothing to lose.

EDIT: Looks like 4 weeks of daily 3 gallon water changes will put me at 95% new water.

 

Ok well then you could not have released a bubble of hydrogen sulfide when you moved the rocks.

Sorry, I know how frustrating it is. Been there, done that and I'll probably do it again.

 

Would that have a lasting effect on only Acropora? The montipora, seritopora, LPS and soft coral seem fine. Fish are happy and healthy too.

 

I decided to frag last night, followed by a water change. Some pieces decided to RTN, other pulled through for now.

valida is almost gone, millepora is gone


This valida is gone


Red planet is on it's last leg. I just got it to start growing two months ago after having it 8 months.

 

So after fragging my corals and removing my dead corals, I noticed that they tended to be a little crumbly. I decided to take a sample of water to my office and measure the pH using a multi-thousand dollar (calibrated) YSI meter.

It began to stablize around 7.5 but slowly worked it's way up to about 7.69.

I think the sheet rock dust fell into the tank and dropped pH, causing my CaCo2 to dissolve a little and cause the STN.

 

damn. that sucks man. at least you came to a conclusion of the cause. it's not horribly low 7.5 but who knows what it was when it first happened.

 

Journal article:

"As mentioned above, there is a critical threshold pH at which calcium carbonate is allowed to dissolve. Determining this value is very important, as it allows scientists to predict when reefs will start to collapse. This value has been found to lie around a pH value of about 7.4-7.66. Recently, experiments have been conducted with the Mediterranean corals Oculina patagonica and Madracis pharensis (fig.5). At a pH of 7.4, these coral's skeletons dissolve quickly; within 4 months 75% of the skeleton had dissolved. We call this phenomenon a negative net calcification, as more skeleton dissolves than is being precipitated by the coral. After exposure to normal sea water having a pH of about 8.2, recovery could be clearly seen (fig.5c)."

 

Alkalinity was 2.72 meq/l or 7.6 dKH

The above is your last Alk value. You need to bring that up to stabilize you pH. While 7.6 is close to NSW, that value can not compensate for other unforeseen factors contributing to a lower pH.

Correct the alk to 9 or higher and you should see the pH stabilize.

Alkalinity represents the hardness, the ability to maintain a stable pH. pH values around 7.8 to 8.4 are within normal range and dependent on the time of day the pH is tested.

You should see a normal swing between the periods of lights on and off. If you're dropping below 7.6 with lights off or during the photoperiod then yes you'll probably see an adverse reaction to your sps.

 

I typically keep it at 3.2 meq/L (9 dKH) which is maintined by my ATO. I never really pay much matter mind to pH as it's pretty irrelevent if your water chemistry is maintained at correct values. I know alot of people struggle to keep pH at a desired level and do more harm than good.

However, if something like concrete drops into the tank, the levels can throw themselves completely off.

I am going to test alkalynity and pH again before I make any changes.

 

So here's my pH reading on a multi thousand dollar meter calibrated to 3 different standards.

Next question: how do I raise my pH if alkalinity is 2.8 meq/l?