Try the PPS pro method to make DIY fertilizer solution. I just planted a tank with Iwagumi scape. I am doing a dry start with Glosso. I am Planning to use PPS pro method, as that works for me with my other tanks.
Glosso likes ammonia. Root tabs help it immensely. IME when growing glosso in aquasoil it goes down hill very quickly/gets very scraggly after 3 months when the nitrogen in AS is depleted. Regular addition of osmocote rescues it nicely but it is a bit of a chore.