FOODS FOR AQUATIC LIVESTOCK
Frozen foods are one of the most popular
dishes, preserved in the best possible form for aquatic livestock. It tastes,
to our pets, just as good as live food and is also a good substitute for those
live foods currently unavailable at our local aquatic retail outlets.
mentioned previously in one of my articles, my Weather loaches had a preference
for worms such as glass worms, bloodworms, tubifex, earthworms etc. Glass worms
and tubifex are not available all year round so the frozen versions of these worms
are fed as an alternative to the real thing, which my Weather loaches still happily
accept. In addition to this my African Clawed Toads, African Dwarf Clawed Toads
and Axolotls love tubifex and they are fed on the frozen versions as well.
some of my friends have cast doubts on the reliability of common frozen foods
I decided to do some research on this matter and explain my findings. During my
spare time have been travelling around, phoning around, writing to and e-mailing
fellow aquarists' gaining advice on the reliability of frozen foods, also doing
my own research in conjunction to contacting others.
The issues of frozen
Frozen foods will kill pathogens but many pathogens can also form
spores which are resistant to freezing. Although the risk is small an introduced
pathogen could cause disease in livestock.
Another matter is that bacterial
problems are also associated with frozen foods. This does not come from the actual
freezing process itself, but from the fact that every time the food is moved from
one place to another e.g. from wholesaler - to retailer - to aquarist (and despite
all precautions taken), there is a very slight defrosting of the food, and this
Another concern, and a much debated issue for a long time,
is tubifex. I myself have fed live, frozen and freeze-dried versions and have
never encountered any problems. This is because my suppliers have, so far, been
reliable. The problem with tubifex is that these worms are collected from very
dirty areas and carry bacteria and viruses. This is why there are now frozen,
freeze-dried and gamma-irradiated versions of tubifex.
to my experience with frozen tubifex in particular, it can make a mess in the
aquarium (mainly causing cloudiness) when it starts to thaw and when a feeding
frenzy occurs in the tank - because this food is well loved by many fish and other
aquatic livestock. But if you have a good-strong filter then this shouldn't be
a problem. In smaller aquariums frozen tubifex can cause more cloudiness in water
so I prefer to feed either half a tube of frozen tubifex or turn to the freeze-dried
form (depending on how many animals are in the tank and how much food they need).
For example in one aquarium I have a small number of fish so half a tube of frozen
tubifex is fed while the other tank has more fish residents so I feed freeze-dried
tubifex to minimise the mess as a result of feeding tubifex.
is when a weekly water change is due in my aquarium, I feed frozen tubifex and
after the fish have fed, a water change is performed as that way I get to carry
out the weekly maintenance and to siphon out the mess produced by the tubifex.
This action also removes the cloudiness as well.
If you are still worried
about frozen foods introducing health risks in your aquarium, then you can feed
freeze-dried foods which are a good substitute such as krill, daphnia etc. But
too many dried foods can constipate fish so you can also try Gamma-frozen foods
- which are the best alternative. I myself feed only freeze-dried tubifex and
bloodworm to smaller fish, and not any other dried food, due to the reason mentioned
During the many years I have fed frozen foods to
my aquatic livestock have never come across any problems. Gamma-irradiated frozen
foods, which some of my friends strictly feed to their fish, are mainly for marine
species, but can be used for non-marine aquariums such as freshwater tanks housing
goldfish. At the end of the day the aquarist must make the final decision as to
which form of foods to feed but, as we have seen, frozen foods continue to play
an important role in the diet of aquarium fish and my personal opinion is that
this form of food carries very little risk to our 'finned friends' and other aquatic
By Majid Ali, Ryedale Aquarist Society
Thank You Majid Ali for allowing us to use your article.