I've been using Revive and Melafix (pond) lately and haven't had any bug/pest issues yet. Melafix is similar to Expel, but much easier to get and much cheaper. There are three versions of Melafix.... regular, marine, and pond. They all differ in the concentration of the active ingredient, so you need to mix them at different rates. Melafix pond is the strongest concentration, so it's what I use.
I mix 6 ML Melafix Pond with 1/2 Gal saltwater. (12ML per Gal)
and dip for 10 minutes, but have gone longer without issue.
Then I dip in Revive (2 caps per 1/2 gal) for 15 minutes. (per bottle instructions)
For dipping frags, I usually float the frags upside down, over an air-stone, in a narrow cylindrical container, ie a skinny bucket. The skinnier the bucket the better, uses less dip and it keeps the frag floating directly over the air-stone for best agitation. or you can go to town with a turkey baster. I just use a little Styrofoam block, stick the frag in and float it upside down. The air stone keeps it all circulating.
For the Melafix, you have three versions, with varying concentration of the active ingredient.
Melafix @1%, Melafix Marine @1.25%, and Melafix Pond @5%.
For a coral dip, below are the recommended mixing rates for each version.
- Regular (1%) 62.5mL/Gallon
- Marine (1.25%) 50mL/Gallon
- Pond (5%) 12.5mL/Gallon
I dip every frag in these.