is exacerbated by many shippers sending
these animals without water. While they
can survive this—and sure, it does save on
shipping weight—it makes their acclimation
that much more difficult. And when they’re
purchased at the local fish store, they may
have just arrived, resulting in animals that
have gone through two rapid changes in a
short period by the time they’re in your tank.
Stocking-level recommendations for these
animals are often ridiculous—I’ve seen
aquarists being advised to keep several snails
per gallon! Start with one per every 5 to 10
gallons ( 20 to 40 liters), depending on how
bad your algae problems are, and add more
snails as time goes on. If they’re overstocked,
they’ll simply starve to death.
Tang with HHLLE
Can anyone tell me why my poor
tang died? She developed a big
hole on her side, and I’m so sad!
The fish you posted a
picture of is a Pacific blue tang
Sometimes the disease clears up on its own,
just leaving the fish with scars, but more
typically it will kill them. I’ve seen it set in
shockingly fast and once watched a perfectly
healthy-looking Pacific blue tang seemingly
deteriorate in front of my eyes.
Unfortunately, there’s not a lot of consensus
on the cause. I think this is due to the fact that
HHLLE is not a disease, but a symptom, and
as such is caused by a number of problems;
it’s like asking what causes a runny nose—
allergies, illness, spicy food, stubbing your
toe, emotional stress...
There are a few studies “conclusively”
linking HHLLE to the use of activated
carbon, and a few more “conclusively”
linking it to stray current in the aquarium.
Both the use of finely powdered carbon and
improperly grounded aquariums do seem
to be contributing factors. Poor diet also
contributes—tangs need to eat constantly
and require a diet rich in marine algae and
zooplankton. This is a tough diet to replicate
As photosynthetic invertebrates, zoanthids will rapidly respond to changes in tank lighting.
Turban snails (Trochus sp.) are often bought as algae-grazers.