A dedicated fish health lab, a closer look at our intake and treatment systems, and the first batch through the new room.
If it’s been quiet around here, this is why. I spent the last couple of months turning a corner of my basement into a dedicated fish health lab. It’s the first time QT Lab has had a room built just for this work, and I’m pretty excited to show it off.
The intake and treatment systems
The back rack is where new fish start. It’s one connected system: a 40 gallon breeder up top, four 20 gallon tanks in the middle, and a 40 gallon sump underneath. There’s room to grow, too. I can add a second breeder up top, and another 20 or a couple of 10s in the middle.
Why connect them instead of running separate tanks? Two reasons:
Time. One system means one set of water changes, one place to test, and one place to dose.
Biology. A shared sump means there are enough nitrifying bacteria to handle everyone’s bioload. This matters most right after a new batch arrives, when a small standalone tank can spike ammonia fast.
The trade-off is that the tanks share water, so I treat the whole rack as one unit. That’s why I built it to come apart. The plumbing is modular, so a tank can be pulled out and sterilized, or the whole system can be broken down and bleached between batches.
For filtration, there’s:
a filter sock and a protein skimmer
a bioreactor running media that’s already seeded with nitrifying bacteria
an auto top-off to keep salinity steady
Every tank is painted black on three sides, which helps nervous new arrivals settle in. Colorado winters aren’t awful, but they can drop, especially in a basement. So there’s a 600 W heater on the system, plus extra aeration to keep oxygen up when treatments or warmer water lower it.
The rest of the room
The second rack is for fish that need one-on-one care, like individual treatment or help with feeding. It may also hold the tool sterilizer.
The microscope and stainless steel work table are where samples get collected, prepped, and looked at. Both get sterilized between uses.
The fume hood is for formalin baths, which you don’t want to be breathing.
A dedicated fridge keeps fish food in the lab, so I’m not moving it in and out of the room.
A dedicated sink makes handwashing part of the routine. This is important: hands are washed with soap and hot water before entering or exiting the room.
What’s not in the picture yet is the medication-free observation space where fish go after treatment. That’s still being built.
How we’re approaching quarantine
I know this isn’t the typical marine QT protocol. Most of the hobby runs every fish through the same set of medications on a fixed schedule. We’re trying something closer to a fish health lab: look first, then treat. Each batch starts with skin, gill, and fecal microscopy, and those results shape the treatment plan, which I put together with our consulting aquatic vet. Then we retest to confirm the treatment worked. The aim is fewer unnecessary medications and less stress on the fish, while still being thorough.
This is still a work in progress. How deep the testing goes depends on time and budget, and I’ll keep adding to it as the lab grows. You’ll be able to see what was done for each fish in its file.
Meet Batch 0x02
The first batch through the new room includes:
Tomini tang
Strawberry dottyback
Marginalis butterflyfish
Yellow-flanked fairy wrasse
Heniochus butterflyfish
Canarytop wrasse
Ornate leopard wrasse (x2)
Midas blenny (x2)
To be upfront: we lost three fish in the first few days after arrival. Early losses like this are part of why quarantine exists. They’ll be noted in the batch file along with what we learned from them.
The rest are settling in, and you can follow along here:
More soon,
Ashwin
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Quarantine reduces risk but cannot guarantee freedom from disease or long-term survival. Availability may change. Site information is educational and is not a substitute for veterinary advice.