When to QT, and when not to

imDarrin · Jul 24, 2026

I have a small AIO 5gal tank that has live rock, live sand and a handful of coral.
I'd like to add a hermit crab and pistol shrimp, but wondering if QT is necessary? Mixed answers on google, so thought I'd reach out to the experts.

Thank you all ahead of time.

Fish Fan · Jul 24, 2026

The title of this thread could blow up the forum

I'm a big believer in QT'ing everything "wet", including fish, corals, snails, shrimp, you name it. This requires several, separate tanks.

But for a 5 gallon pico, that I'm assuming has no fish (and I would not suggest fish in a 5 gallon), I probably wouldn't worry too much. The only concern would be coral pests, and I guess you could do a coral QT tank for a 5 gallon coral DT, but in this case I don't think the juice is worth the squeeze. If a 5 gallon coral tank gets infected with anything, I'd just start it over, as crass as that sounds

I think you should just add your hermits and the pistol shrimp, likely you'll be fine, and if you get coral pests they can be dealt with, or you can simple reset the tank.

Good luck!