What Are These Small White Worms?

Another "How-To" By Jeff Snyder...and he ought to know! :)


Some time after setting up an aquarium - it can be weeks, or even months --
the aquarist will discover small, white worms floating in the water, on the aquarium decor, or crawling on the glass panes of the tank. These tiny, thread-like creatures are so small -- usually only a few millimeters in
length at best -- that it is impossible to make out their delicate features.

Exactly what are these worms; and more importantly, do they pose any danger
to your livestock?

If you discover these creatures in your aquarium, it is probably an
infestation of a non-parasitic flatworm known as Planaria. Planaria are
found in many parts of the world, and thrive in both freshwater and marine environments. In fact, some species of Planaria are terrestrial in nature,
and are capable of living in humid areas in the soil, under rocks and logs,
and even on plants.

To answer the latter question, unless you are a fish breeder who is raising
egg layers as opposed to mouth breeders, Planaria do not pose a direct
threat to your fish. In fact, some fish enjoy eating them. I often see my
fish pecking at the water as they snack on these minute worms. Smaller fish
-- such as fish fry -- will particularly enjoy eating Planaria, and they
will form a staple part of the fry's diet. On the other hand, if you are breeding egg layers, be advised that Planaria do prey upon fish eggs which
are laid upon rocks, plants and the aquarium substrate.

While generally-speaking, Planaria do not pose a direct health threat to
your fish, it is important to note that the presence of Planaria may be symptomatic of another problem which exists in your aquarium; and this has
to do with the level of organic waste that is found in the tank. In order to thrive, Planaria must have a food source; and this food source usually comes
in the form of uneaten fish food which settles in difficult places, such as between rocks and other aquarium decor, in the sand or gravel bed, etc. Of course, aquarium filter pads also provide an excellent feeding ground for minute aquatic creatures such as Planaria.

Aside from the fact that uneaten fish food and other organic matter provides
a free lunch for organisms such as Planaria, if left unchecked, a buildup of these substances can result in a dangerously high concentration of nitrate
in the aquarium. High nitrate levels can contribute to stunted fish growth,
as well as other fish maladies, such as fin rot.

In short, the most logical way to reduce the number of Planaria in an
aquarium, as well as to retard the development of nitrate in the aquatic environment, is to simply exercise more restraint at fish feeding time. Just like people who become attached to other kinds of pets, we tropical fish hobbyists sometimes worry that perhaps our fish aren't getting enough to
eat. As a result, sometimes we tend to be too liberal at feeding time. Don't
do it! You are just asking for trouble!

While people who are new to the fish hobby may not realize this, two light feedings per day -- what the fish can eat within a few minutes -- is more
than sufficient for our aquatic pets; and any more than this can in fact be harmful in a number of ways. Unlike some humans who feel that they are "starving" if they go even one day without eating, fish can go several days
-- or longer -- without any apparent ill effects to their health. In fact,
it may surprise you to know that certain species of fish -- such as cichlid mouth breeders -- go up to three or four weeks without eating, while they incubate their spawn in their mouths.

In addition to cutting back during feeding time, there are other steps which you can take to reduce, or even to eliminate, Planaria from the aquarium. Following are some of them:

1. One option is to use a chemical-based agent to get the Planaria under control. While I am mentioning this solution here, allow me to clarify that
I have not used any chemical-based solutions in my aquariums in years. There are several reasons why I have adopted this approach. Quite simply, any time you add a chemical agent to an aquarium, you are facing the risk of substantially altering the chemistry of the water, as well as upsetting the ecological balance of the aquarium as a whole. Different aquarium species -- both plants and fish -- have different tolerance levels for chemical agents. What may not affect one, will seriously affect another, and possibly even
kill it. Thus, breaking just one link in the ecological chain, could result
in serious detrimental effects in the aquarium as a whole.

2. Whether or not you use an undergravel filter, it is a wise practice to siphon decaying detritus from the aquarium substrate -- gravel or sand -- on
a regular basis. There is a wide variety of gravel washers -- or gravel
vacuums -- on the market. Choose one which meets your needs, based upon the size of your aquarium, the depth of your gravel bed, etc.

An alternative method -- which I personally employ -- is to use a turkey
baster to stir up the substrate, and to "dust off" the rocks and other decor
on a daily basis. Once the detritus is free floating in the water, it can be sucked out of the tank by your external filters, assuming that you are using some in your aquarium setup.

3. Change and/or clean your filter pads on a regular basis. Not only will
this practice reduce the food source for the Planaria, but it will also help
to keep your nitrate level under control.

4. Conduct partial water changes on a regular basis. Not only will regular water changes help to lower the concentration of nitrate in the aquarium,
but it will also remove many Planaria -- and possibly Planaria eggs -- which may be free-floating in the water. Regular water changes may also motivate
your aquatic friends to spawn. At the very least, it will liven them up. The norm is to change 25% of the total water volume -- or more -- on a weekly basis. If your Planaria infestation is severe, and/or your nitrate level is high, you may even want to consider two water changes per week until you get the situation back under control.

5. Another possible solution -- which I personally have never tried -- is to add one tablespoon of marine salt per five gallons of actual water in your aquarium. In other words, just because you have a sixty-gallon aquarium does not mean that it holds sixty gallons of water once it is all set up. You
will simply have to calculate how much water is displaced by aquarium decor
-- such as substrate and rocks -- and then base the amount of salt used on
the approximated amount of water that is actually in the tank.

Important: A word of caution is in order here. While you may become fed up
with the Planaria problem, and decide to tear down the tank and thoroughly clean everything, this is not a wise solution, particularly if you have a well-stocked aquarium, and there is no other safe place to put your fish for
a few weeks.

As you may already know, and as I explain in my post "How To Eliminate
Algae", in an aged aquarium, certain strains of beneficial bacteria -- known
as nitrosomonas and nitrobacters -- exist. These bacteria are responsible
for converting -- or oxidizing -- dangerous ammonia into nitrite, and then nitrite into nitrate. Without these bacteria in the aquarium environment,
your fish would die within a matter of days or weeks at best, due to the
high level of ammonia. A brand new aquarium setup does not contain these bacteria in significant numbers, and neither does one which has just been
torn down and cleaned up...unless you are knowledgeable and have taken
certain steps to replenish the bacteria quickly.

The point is, if, in your quest to remove the Planaria from your aquarium,
you tear down the tank, clean up everything, put everything back together,
and place the fish back in the tank, you may end up with a worse problem
than the Planaria ever were -- namely dead fish!

In short, I would only advise tearing down a tank in this manner, if you
have another already-established aquarium of sufficient size where the fish
can be safely housed until their original home is set back up and aged properly.

I hope that the above information is useful to you...and may your Planaria
be few! :)



Jeff Snyder, SysOp - Armageddon BBS Visit us at endtimeprophecy.org port 23 ---------------------------------------------------------------------------- Your Download Center 4 Mac BBS Software & Christian Files. We Use Hermes II


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