Dear Dr. Ghoti,
I have an octagon aquarium in my living room which is too close to the
window and has gotten a lot of algae build-up in it. At first the
water turned green (really green) but that went away (why?). Then
algae started growing on the sides of the tank but I figured it was
good for the tank and I left it alone, except for the front which I
scraped. The algae was brown at first but then it started to turn
green. Then it got really thick and finally it started peeling away
from the sides of the tank. Now the people at my local fish shop say
to scrape it off because it’s bad for the fish, but they are the same
people who told me to let it grow because it was good for the tank. Do
they know what they’re talking about?
Slimy in Nanaimo
Dear Slimy:
When your tank turned green it was due to a bloom of free-floating algae. The people at the fish shop told you to not clean the glass because algae growing on the glass can out-compete the green water type. Sounds like it worked. The brown algae is a type called diatoms, one of the first to get established in an aquarium and one of the easiest to remove. The reason they told you to remove the green algae is probably because they suspected it was a species of blue-green algae (Cyanobacteria) that are not strictly photosynthetic but which thrive on organic material such as uneaten fish food or fish feces. That means that they are not necessarily removing waste products from the water but may actually be contributing to the waste load of the tank. Once the blue-green algae starts to peel from the tank it is a sign that it is suffocating itself --- it has gotten thick enough that the cells on the glass aren’t getting enough oxygen (and this type consumes oxygen) or nutrients to survive. Dead algae, and other dead stuff, pollute water. Yes, let it grow--- then scrape it out and throw it away. Blue-green algae does best when you overfeed the tank, don’t do water changes, and have plenty of calcium in the water.
Dear Dr. Ghoti,
I am a student in the College of Fisheries at the University of
Washington. A few years back, I spoke with an Icthyologist at the U
about the tropical fish hobby and she told me that she found it very
irritating that aquarists insist on using common
names to describe
fish instead of using their correct scientific names. She says that a
lot of confusion would be avoided if people would simply take the time
to learn the correct scientific names of the fish they are dealing
with. Why don’t aquarists educate themselves?
Wondering in Wallingford
Dear Wondering,
I’m always one of the first to criticize hobbyists for not learning about the animals that they keep, but in this case I have to stand up for the aquarist (a person that does seek to learn about aquatic life through aquarium-keeping). Aquarists go to great lengths to learn the names of fish and to identify them correctly. They don’t often get much support from the scientific community. A guppy will always be a guppy, though the name has been changed from Lebistes reticulatus to Poecilia reticulatus. Most aquarists known a Ram cichlid when they see one even if no one can decide if the genus name is Apistogramma, Microgeophagus, or Papillochromis. Who cares? It’s a Ram. Many time we aquarists find that a common name is the only name we have because the species hasn’t been given a name yet. The Electric Blue Haplochromis is a good example... bred in captivity and distributed around the world for years before it got the name Haplochromis ahli.
Dear Dr. Ghoti,
About two months ago I set up a new tank. It’s a 20 gallon, with
livebearers, angelfish, neons and Corydorus catfish. It has an
undergravel filter, new quartz gravel (pink), and is heated to 76
degrees with a Supreme(TM) 50 watt heater. There are no live plants in
the tank, just plastic. I use Novaqua(R) to condition the water when I
do water changes (5 gallons a month). Everything was going fine until
a few days ago when some of the fish started showing signs of
fin-rot. I got some medicine from my local fish shop but the fish
started getting worse. Most of the neons have died and the angelfish
are up at the top all the time, except when I feed them. The catfish
are hovering in mid-water and their whiskers seem to be burnt off. I
lost two of the livebearers (patties) and the others are kind of
twitching. Am I using the wrong medicine or did I use too much?
--Nana Chromis
Dear Nana,
The signs you describe are typical of New tank syndrome
in which
the ammonia reaches dangerous levels in the first month or two after
the aquarium has been set up. You probably have an ammonia problem. If
you’ve done any water changes yet that has helped to delay the onset
of ammonia poisoning but it finally caught up with you. You need to do
another water change, probably 50%. Also, it would be a good idea to
use one of the biological conditioners, such as Fritzyme(R) or
Nitrovec(R), to help get the ammonia-eating bacteria (Nitrosomas and
Nitrobacters) established in your filter. Unfortunately, you may
experience continuing problems of this nature, because quartz gravel,
especially artificially-colored kinds, are not conductive to the
growth of beneficial nitrifying bacteria because of the low mineral
content and toxicity of the coloring agents used. Lastly, the
medicines that you added probably made things worse by killing off the
little biological filtration that you had. I would change the gravel
to a natural
type and start checking the pH on a regular
basis. You would also be well-advised to get an ammonia test kit.
Steve Ward has been a member of GSAS since its inception in 1971. He can be often found working behind the counter at B&D Aquarium, where he would be delighted to sell you an ammonia test kit.