I am Peeved - Salt Mixture Causing High PH?!

[bheron]

For months I’ve been trying to lower my PH and find out what’s causing the problem. It’s been around the 8.6-8.8 range and killing any inverts and, I think, growth on my live rock.
I believe now that its my Sea Salt Mix.
I do water changes with RO water. At 62 degrees F the PH of the RO water measured 6.8. However, after adding my Sea Salt Mix it jumped to about 8.9-9.0!! This can’t be right?! I know PH is different at different water temps so maybe tonight when my mix is heated to 79 degrees it’ll change somewhat.
But I think it’ll still be high meaning that all along my Sea Salt Mix has been messing up my tank big time! Has anyone heard of this before? I can’t remember the name but I believe it’s a reputable brand b/c I’ve seen it for years – white bucket with purple and black logo and writing on the bucket.
Please let me know what you think.

 

[alti]

how long do you mix the saltwater before you testes it and before you added it to your tank? the salt mix should not raise the ph too high. are you adding anything else to your tank?

 

[bheron]

I just tested it last night, 24 hours after I added Salt Mix to RO water, aerated it, and raised temp to 79. I added NOTHING else and the PH read 8.6-8.8 last night! So it IS my mix - all this time!

 

[thomas712]

I had that happen once with one bag of salt that I was trying, didn't like the results so went to Instant Ocean. I do not remember the exact changes but it was sure enough to freek me out when the fish started jumping damn near out of the tank. Found out my ph was bummped way up.
Thomas

 

[birdy]

If I were you I would try a different brand of salt maybe you got a bad batch.

 

[ophiura]

Wow. Have you been using the same bucket all this time? I think it is what, 250g or something, so I bet yes. What brand was it?