Those sea horses are looking good mate! Does the Nano produce much smell outside?I do the same , feeding Nano that is along with a tiny bit of Vodka dosing to boost bacterial levels. (my phosphates are still high) I also dont run a skimmer....oh and from time to time i dose with bread yeast too :).
I can help out with Nano if anyone is wanting some too on the goldie.
Below is my third Seahorse fry batch in their fry catcher tank. I am going to be going Chris's way and doing the green water outside...i just dont have enough to keep it up to them growing it on the window sill.