new 75g reef tank

[reefmaster70]

Hey all. I've been keeping a 20g Nuvo reef tank now since January, and super successful, and I love it. I am not new to the hobby, had a large 120g back in 1997 to about 2004.

Anyway, I decided to set up a larger tank again...a 75 gallon. Anyway, I pre-cured my live rock and live sand in my garage in some rubbermaid totes for months, so I'd have a minimal cycle when I set the actual tank up. It worked well. I set the display tank, the 20g sump up, and all equipment about 2 weeks ago now. I measured Ammonia, Nitrites, Nitrates daily until the Ammonia and Nitrites dropped to 0ppm. Now I only have Nitrates reading about 35ppm and my Phosphates are reading about 2.51ppm. My pH has been creeping UP the last week to today it is at a pH of 8.5 (started out right around 8.0)

My questions are: Why am I seeing significantly high measurable phosphates and a pH that continues to creep up? My 20g Nuvo is literally about 30ft away and I struggle to maintain a pH of 8.0 on that one, and it seems this new 75g is taking care of pH all on it's own.

Was wondering if anyone can help me out on the Phosphate and pH concerns?? I am planning to just let it ride for another week or so, before I do a 10% water change and see what the numbers continue to do.

Thanks

 

[Subsea]

Are you running lights on 75G setup?

What was phosphate reading on cycled Rubber Maid tote tank?

 

[reefmaster70]

Nope, no lights yet, other than general daylight in the room during the day. Never checked Phosphates while rock was cycling

 

[reefmaster70]

And I'm not overly concerned with Phosphates. I know how to handle those and reduce them. It's the continuing climb of the pH that has me perplexed.

 

[Asif Iqbal]

Have you recently calibrated your probe. My guess is you did and it is likely a new probe with your new setup.

 

[Subsea]

And I'm not overly concerned with Phosphates. I know how to handle those and reduce them. It's the continuing climb of the pH that has me perplexed.

Normally, high pH means limited carbon dioxide. Considering that tanks are in same area, what else would limit co2 gas exchange on 75G tank?

 

[reefmaster70]

Have you recently calibrated your probe. My guess is you did and it is likely a new probe with your new setup.

it was calibrated about two weeks ago. It's not a new probe however. It's fairly old. I did use my Salifert pH test kit this morning to double check readings, and the test kit is reading approx. 8.4pH. which is less than the 8.6 the probe is currently reading. I'll calibrate the probe again and see if it changes. If not, I do have a brand new pH probe I can switch out.

 

[NeedAReef]

get an independent lab test done for about 50 bucks... will tell you a lot and give you a good starting point. look around here for good recommended labs.