All three can work but be careful when using them and use them sparingly and only when needed. Mites build resistances very quickly so it is really important to rotate what you are using. Ideally you should only be using one miticide a few times a year. So for example if you sprayed with
Avid once, next time use
Floramite, and the time after that use the
Forbid. It is also important to make sure the different miticides you are using have 'different modes of action.' Or in other words, make sure they kill the mites in different ways so they are less likely to build resistance.
Be sure to invest in proper protective equipment as well - you will want a full chemical suite and a full face mask respirator with an organic vapor cartridge. I always like to spray chems like this outside, rather than in the grow room to keep residue and potential contamination to a minimum. I see a lot of people who will wear protective gear when they first apply a product inside, but then will be right back in their room with no protective gear the next day. Well guess what if you just covered your entire room with something that has a two week half life, you are exposing yourself every time you go back in there.
These products can be useful and effective but I think a lot of time people tend to try to down-play their potential health effects. Bifenazate, the active ingredient in
Floramite is a suspected reproductive toxin and endocrine distruptor as well as a potential ground water contaminate. Abermectin, the active ingredient in
Avid is a known reproductive toxin and endocrine distruptor and on the Pesticide Action Networks (PAN) list of 'Bad Actor' chemicals. Spiromesifen the active chemical in
Forbid has no available
weight-of-the-evidence summary assessment so its potential health effects are not very well known.
You might also look into other miticides as well. There are some out there that are in my opinion a bit safer, and still effective, such as Akari. UC Davis has several other options listed on their website:
PROPARGITE (Omite)
FENBUTATIN-OXIDE (Vendex)
FENPYROXIMATE (Fujimite)
PYRIDABEN (Nexter and Pyramite)
ABAMECTIN (Agri-Mek)
NARROW RANGE OIL (Saf-T-Side, etc.)
INSECTICIDAL SOAPS (M-Pede)
NEEM OIL (Trilogy)
HEXYTHIAZOX (Savey)
DICOFOL (Kelthane)
Just be safe and smart with what you use, don't be a pesticide retard like so many other people are!