The study by Pinti et al provides a detailed analysis showcasing the importance of fish and other metazoa in the global ocean carbon cycle. This is an important study as it goes beyond just looking at zooplankton to also quantifying contributions of higher trophic levels. The modelling work is also able to capture the diel vertical migrations of different organisms, which is not a trivial process to express computationally. The paper is very well written with clear figures and logical conclusions and is an impressive amount of work. I believe this work will make a valuable contribution to the scientific community. I have very few comments:

- The authors state in abstract the paper is of global scale, and in the paper acknowledge it does not cover the poles. i think this should be mentionned upfront to make sure readers are aware of this early on. The poles are important in cycling of carbon with large biomasses of metazoa (e.g. Yang et al 2022).

- line 143, do fish ingest zooplankton in the mesopelagic or only at surface? How have you defined strongest trophic coupling?

- line 170 - define efficient, what does it mean in this context? Arguable most efficient is from primary production conversion of CO2 to organic matter, and then final sequestration.

In this work, Pinti et al try to identify taxa and pathways mainly involved in carbon storage using a pelagic food web model. This is an important topic and an excellent scientific work. There is no doubt that this paper will be of strong impact in the scientific community. I especially appreciated that the authors take into account functional groups including jellyfish and the potential impact of bathypelagic fish in the discussion. I also appreciated information provided in the supplementary materials but felt a little bit difficult to read the main paper without the model detailed in the main text. 

Very minor questions/comments:

• Is it possible to have more than one Nash equilibrium in this case?
• The comparison with Nowicki publication seems to have a major difference without fish and jellies which can strongly modify the similarities between these works. This is notified but I am not sure if the comparison of figures between these two works is realistic then.
• The discussion about how this work could provide baseline for future assessments for fishing (L263 and then 323) is extremely short. In particular, the authors state that the main uncertainty in their work is about mesopelagic fish biomass. This potential bias is taken into account and highlighted at the beginning and in the discussion, and by doing so they highlight the need of a better estimate in biomass. Could you develop a little bit based on your model results what would happen for carbon sequestration if you decrease the biomass by 50% as mentioned from St john2016?