New to SPS,help ID these

[m1923]

The one in circle was blue, but after two weeks ,it becomes purple,is my NO3 too high? Somehow My test NO3 is almost 0, maybe something wrong with the test toolkit?

Thx for help!

 

[m0jjen]

PO4? What type of light did i come from? What typ are you using?

 

[Diesel]

Nope, if your No3 is almost 0.0 than you're to low on nutrients.