I have had multiple fry nets hanging in my 46 gal tank for over two months now. It is frustrating to only be able to change out 5 gallons of water at a time. So my dad suggested I get some sort of container to sit the nets in while I change the water.
I found plastic "shoebox" containers for under a dollar each that are big enough to fit a net each.
You get the container into the tank and carefully scoop up the net so there is always water in there for the fry. Then carefully remove the container complete with water, net, and fry to another location. You can now do as big of a water change as you want without worrying about jostling the fry or keeping the water level above the bottom of the nets.
After the change is complete you can float the container in the tank and slowly mix the new water with the old to acclimate the fry before lowering the net back into place.
No more doing 3x the work to remove the same amount of nitrates.