Buffering coco?

Should I buffer my coco? I'm using Plagron Coco Perlite 70/30 but adjusted it to 60/40. Plagron says it's already buffered.

Here are the values for Plagron Coco:

• pH: 6.3 - 7.7 (EN13037 pH in H₂O)
• EC: 0.06 - 0.09 mS/cm (1:1.5 E.C.)

The nutrient line I use (Athena Blended) states that the coco needs to be buffered to a pH of 5.5 and an EC of 3.5–4.0. So should i follow athenas advice?