My smallest Opae tank, thriving for three years

[Corucia]

I wanted to share the smallest Opae tank that I’ve set up, which uses a diminutive lab reactor (5000ml / ~1.3 gallon). It’s been running for about three years and I originally established the ecosystem using water, algae, snails, amphipods, copepods and larval-stage Opae Ula from my other tanks, so it’s 100% homegrown. The population has bred a couple of generations of new Opae since it was set up, and I just noticed a new berried female so more babies are on the way!

[Aquarimax]

It is fun to see so much variety in an obviously successful, yet diminutive, setup.

[John]

Hi Corucia! Awesome tank! Thanks for sharing! Where did you get those amphipods? Are they a marine or brackish water species? Did you notice that the amphipods compete with the shrimp for food?

[Corucia]

Hey John. I picked them up from Aquarium depot (see https://aquariumdepot.com/amphipods-cop ... =Amphipods). It was an assortment of amphipods and copepods. While not specifically oriented towards brackish water, I’ve found a substantial portion of the amphipods survived and established a breeding population. My most productive tank has many of them that live in the substrate and they haven’t at all impacted the Opae population nor their breeding.

[John]

Interesting! I did not know that salt water amphipods can survive in brackish conditions! That is great!
How often and how much do you feed them since animals tend to outcompete each other if there is not enough food? I am asking because amphipods usually are very aggressive feeders.