Bat guano first timer :O

[HerbCyclone]

Hi (y)all,
I just picked up some bat guano(7-3-1) and high phosphorus seabird guano(0-11-0). In the past I've used chicken or turkey based pelletized fertilizers and I am currently feeding my plants nutri-rich pellets which have an NPK value of 4-3-2.
I'm trying to find a good way to apply these new(to me) powdered guano fertilizers that are pretty notorious for causing problems if not used properly.
This is what is in my mainly soil-less medium(s) per 100 gallon pot:
70% pro mix mycorhizae
20% black gold potting soil
5% additional perlite
8 cups glacial rock dust
15 cups activated bio-char
6 cups fish bone meal(5-16-0)
10 cups chicken compost(3-2-2)
10 cups nutri-rich(4-3-2) pellets
1 cup kelzyne
The mix is incredible light and nearly impossible to compact which was intentional. On the other side of the coin, it seems like a pretty lean mix so I plan on needing to top dress and foliar feed weekly at least.
I don't want to leave out information, and I'm hoping somebody can help advise. Is it a bad idea to use the fossilized seabird guano when I've got decent amounts of slow release phosphorus with the fish bone meal already present?

 

[mysticepipedon]

I don't know about the seabird guano, for this particular mix. Maybe save it for the next soil mix.

During veg, the plants might like the extra N in the bat guano. I can't tell you whether a top dress would burn the plants or not.

BTW, I'm wondering what constitutes a "soilless" mix? The peat moss of the pro mix and the biochar both have a lot of cation exchange capacity and interact with the roots and microbes to supply (or not supply) nutrients to the plant. They also buffer the mix from rapid pH or other chemical change. This is what soil does.

I thought, but may be mistaken, that soilless mixes just provide a physical media for the roots with a good mix of nutrient solution and oxygen. I'd welcome any comment on this.

 

[HerbCyclone]

During veg, the plants might like the extra N in the bat guano. I can't tell you whether a top dress would burn the plants or not.

BTW, I'm wondering what constitutes a "soilless" mix? The peat moss of the pro mix and the biochar both have a lot of cation exchange capacity and interact with the roots and microbes to supply (or not supply) nutrients to the plant. They also buffer the mix from rapid pH or other chemical change. This is what soil does.

I thought, but may be mistaken, that soilless mixes just provide a physical media for the roots with a good mix of nutrient solution and oxygen. I'd welcome any comment on this.

My gut is telling me the seabird guano is risky, so I might just omit it. Less is more when the alternative is N or P burn.
I thought coco/perlite and peat or spagham/perlite constitutes a soil-less mix. I added the bio char to increase microbial fertility since I'm using organic fertilizers, but the mix is fairly inert as the 15 cups is a mere drop in the bucket with my 100 gallon pots.
I think you're right though and I may not be able to call my mix soil-less as it is more of a hybrid.