Ocean water and PH issue

[ninjamini]

Does anyone have any issues with buying ocean water and PH?

My PH is 7.8 at 82 degrees. It has been this low before and I used a buffer to bring it back to 8.2. Now its back at 7.8. What would cause it to drop. I use ocean water that I buy local. I just tested that and it is 7.8 at 73 degrees. I dont heat my water till I'm gonna add it. I did 2 10% water changes to get my nitrates down this week. I had a nitrte spike to 40ppm. Here are my perimeters:

Amonium - 0
nitiite - 0
nitrate - 20
PH 7.8
calcium - 500
kh - 110
po4 - .1
did I forget anything?

Should I just keep buffering it or is there some cause that I can fix? Or should I just leave it at 7.8. I house all kinda of corals including some LPS and some SPS.

 

[Rogger Castells]

You forgot to post your alkalinity. The 7.8 ph it is not that bad, assuming you have a high alkalinity (dkh)
How are you testing calcium? what are you using to add calcium?
What ever you are doing for calcium addition, I would lower the dossage and you will see an increase on the ph, you should really try to maintain the calcium 420-450.

 

[frh674]

where can you buy ocean water? the place I buy from uses salt mix

 

[chrisaggie]

Try putting an aireator in a small glass with the tank water outdoors and test the pH then.

 

[nyvp]

Many of the stores sell Ocean water. I know coral reef farm on stirling does.

 

[ninjamini]

<a href=showthread.php?s=&postid=8911441#post8911441 target=_blank>Originally posted</a> by Rogger Castells
You forgot to post your alkalinity. The 7.8 ph it is not that bad, assuming you have a high alkalinity (dkh)
How are you testing calcium? what are you using to add calcium?
What ever you are doing for calcium addition, I would lower the dossage and you will see an increase on the ph, you should really try to maintain the calcium 420-450.

I thought that KH at 110 mg/liter is good. The test kit says 105-125 is normal for Salt water. I also thought calcium should be between 400-500 mg/liter.

I may be wrong and please correct me if I am. If they are correct could circulation increase ph? How?

Also know that I have only added chemicals to this tank 3 times in 6 months. I used a ph buffer once and used b-ionic 2 times. The only other thing I do is a water change every 2-3 weeks. I know I mean to do it every week but...