Tank is crashing :(

[MitchM]

Sorry to hear, iceman86.
A few questions:
Did you measure the PH before and after the addition of the calcium reactor?
Do you have a sandbed?
What light fixtures were you using and which ones are you now using?
What do you have for water circulation?
How much GFO have you been using and how often are you replenishing it?
How long has the tank in it's present state been running for?
Can you post a link to the Walmart nori?

Please post a picture as mentioned above.
I'm not a fan of GFO because it will remove trace elements, so I would recommend a larger (25%) water change sooner than later.