That's good.
Take note that you have to shake the Prazipro well as it's hard to dissolve.
Usually, I will put slightly higher dosage than the instruction given.
And for severe cases, I will doze once every 3-4 days or twice a week.(one in the mid week and another dose after my weekly water change).
You may have to treat them for 1 - 1.5 month as the gill flukes can lay dormant for a long time.
According to some, the eggs may hatch only after some time.
From my experience, I find that the flukes won't totally die off totally when I medicated my tank for 1 month.
And each time the flukes returned, they became immune to the medication.
I used many types of medications [ Praziquantel, Sterazin(Waterlife), Anti-Parasite, Slime, Velvet (Interpret) ] but I didn't succeed in eradicating them from my tank.
I almost wanted to close down all my tanks as I had too many fish that died.
In the end, I only succeeded after using Flubendazole(Wormer Plus) for 3 months straight/continuously.
But there are some people who didn't succeed even when they used Flubendazole.
Hopefully, the Praziquantel can kill the parasites that caused the Whirling disease.
There is a possibility that the flukes infection in their gill may cause the fish to circle around as it caused them much irritation in their gills.(my opinion only).
I listed down some information and medications for your reference.
Gill Flukes & Treatments:
Flukes are a parasite. There are two main families of flukes affecting discus. Gyrodactylidea is a fluke which usually attacks the skin. Dactylogyridea family of Flukes is an egg laying fluke and live mainly on the gills.
www.simplydiscus.com
Flubendazole (NT Lab):
Belonging to the best range of 'Water Treatments' awarded by the Pratical Fishkeeping Manufacturers Poll. Anti-Fluke & Wormer is an easy to use, ready-mixed liquid formulation of flubendazole effective for treating intestinal worms and also for eradicating skin and gill fluke infestations.
www.ntlabs.co.uk
Flubendazole/Wormer Plus:
https://www.amazon.com/dp/B085TQ75Z5/?tag=ff0d01-20
Anti-Parasite, Slime, Velvet (Interpret):
Anti Parasite, Slime & Velvet Plus – 100ml | Eradicates flukes and protozoa. Includes market leading breakthrough formulas for the best results.
www.interpet.co.uk
Sterazin(Waterlife) :
Our tropical aquarium fish disease treatments & vitamins treat white spot, ich, ulcers, fin rot & other fish diseases. Prices from £4.70 - Free UK Delivery
www.allpondsolutions.co.uk