Yellowing in Veg at 1.7 EC??

I don't understand...

I Ph the water down to 5.6 and then it rises to about 6.0 over the course of 24 hours.

There's slight wilting almost constantly, though I don't think that's very dangerous.

I'm using equal parts Grow - Micro - Bloom (GH), maybe that's the problem?

When I raised the EC from 1.3 to 1.7 the other day they showed improvement but that started yellowing again.

The yellowing happens on the bottom fan leaves and new shoots at the top.

The rez is almost 2 weeks old now.

Thanks for your help.

I would assume (I say assume because no info on grow type, hydro, bubble etc, and no pics) that they are asking for more nitrogen. Best do a new rez and set the ratio to more grow than bloom.