I think is not possible to directly help, as we don't know the data, but I tend to be fan of not transforming the data (other than scaling).

I paste a couple of references regarding variable transformation issues, focusing on ecological research:

https://www.nature.com/articles/s41559-018-0610-7

https://besjournals.onlinelibrary.wiley.com/doi/10.1111/j.2041-210X.2010.00021.x

as a simple example on how misleading can be even simple data transformations, and assuming you have in one plot half the biomass than in other...

```
20/40
[1] 0.5
log(20)/log(40)
[1] 0.8120982
sqrt(20)/sqrt(40)
[1] 0.7071068
exp(20)/exp(40)
[1] 2.061154e-09
```

finding the right transformation may be harder than it looks. From these examples, the only one that that can be easily 'back-transformed' is `sqrt(20)/sqrt(40)`

, that goes back to 0.5.

Better check what are the standards on your area of research (and what I know about fish biomass, like growth, it is normally modelled as non linear)

cheers