My tank got infected with hydra after a plant trade. I decided to use meds to eliminate the hydra, since they are, at best, competing with my fry for food and, at worst, possibly preying on or at least stinging the fry. I know that most people seem to be using the canine tabs
, and I have seen comments in this forum suggesting that the liquid form has questionable ingredients that are to be avoided (see inactive ingredient list here
). But I also have goats, so we have the Safe-Guard liquid goat wormer on hand. A little more digging revealed a shrimper who successfully used the liquid goat med to eliminate planaria and hydra while sparing all other inverts
. The shrimper is dosing 2.5mg/gal but the dog pill people are using a dose 4x as high. So, I gave the liquid form a try in one of my tanks, dosing the lower 2.5mg/gal. Hydra gone. Fish fine. Mollusks fine (ramshorns, bladders, ponds, limpets). Worms fine (Grindals and blacks). Copepods fine. Excellent.
Next up was the RCS tank. I know that the dog pill people say shrimp are unaffected at 10mg/gal, and the shrimp guy said his were unaffected at 2.5mg/gal. But this is my 1st group of shrimp, and all 5 girls are currently berried. I don’t want to mess that up! But I do want to get rid of those hydra before the shrimplets fledge. So, I started with 0.25mg/gal, that’s 10% of the conservative dose. Within just a few hours, the hydra shriveled up and the berried gals seemed unaffected. Whew! Oh, there’s an apple snail in there too; not only was it not hurt by the drug, it's been so much more active in its grazing since the hydra are gone. I wonder if they were stinging the snail?
So, what have we learned?
1. The liquid form of the med seems to work just fine despite any questionable inactive ingredients.
2. A dose as low as 0.25mg/gal (1/40th of what is commonly recommended!) seems to be effective against hydra. I wonder how low I can go?
3. A dose of 2.5mg/gal had no apparent impact on fish (and fry), mollusks, worms, or copepods while 0.25mg/gal had no apparent impact on shrimp, including berried females. Note: I don’t keep nerites and other members say it kills them!
Just thought I’d share that experience, for the record.