Safety of Fertilizers in Bioactive Mantid Tanks

[The Mantis Menagerie]

As the title says, I have been working on more bioactive mantid tanks recently, particularly for my Brunneria borealis colony. I think some of my tanks need fertilizing, but I am curious what the consensus is, if one exists, on the safety of various fertilizer types inside a mantis tank. I am not worried about the mantis directly consuming them as even when they drink from mist droplets, these are not usually on the ground. Rather, I am primarily concerned with the possibility of feeder insects ingesting the fertilizer and subsequently transferring it to the mantis. Via biomagnification, this could ostensibly be problematic if done repeatedly.