If you wanted to see more nests in your BH you should look into the use of Super Pheromone and perhaps Love Portion.
I have been following this whatsapp group that are active in trying new ideas.
In the beginning they were testing the love portion but soon they also introduce the Super Pheromone.
From what was tested using both the enhancing liquid the nests number shot up tremendously.
I have not tried the two together but I will as soon as I get my hand a bottle of Love Portion.
Right now I hold a sizable stock of Super Pheromone.
What you can do is either to spray the two on alternate spray basis or perhaps mix the two together.
One very interesting observation made in a BH in Pahang was to spray the two liquid one after another in a BH with a lot of nests.
The tester will spray those empty spots in between two existing nests.
The fist empty spot with SP and the next empty spot with LP.
He continued to do so on all the empty gap and see what happen within a few short weeks.
What he discovered was something very unusual.
All those gaps were filled with nest.
Pretty amazing and unusual.
For this particular exercise the owner used the two liquid in a high populated BH.
He was very excited about it and posted inside the group chat.
He claimed that with the setting of humidifier and application of the two liquid he achieved more nests with grade A shapes.
Let me see if this method is true and if you happen to test please inform me at email@example.com.