Re:Little white bugs?

Pete Giwojna

Dear Haynes:

Don’t panic — most likely those tiny white bugs are simply some sort of harmless ‘pods. Most types of copepods and amphipods are very beneficial in the aquarium and highly desired by seahorse keepers because they are favorite natural foods for seahorses. For this reason, it is customary for many seahorse keepers to order starter cultures of copepods and Gammarus amphipods and introduce them to their seahorse tank or refugium in order to build up a thriving population of the ‘pods.

However, on rare occasions a bloom of cyclopoid copepods becomes a problem. This is a very uncommon situation that sometimes crops up in closed-system aquaria when the population of cyclopoid copepods explodes unchecked. Although the copepods themselves are harmless, when a major copepod bloom occurs the sheer numbers of these tiny crustaceans can physically clog the gills of fishes and result in asphyxia or suffocation. Of course I would be happy to share my thoughts on this matter with you.

For starters, here’s how I described this condition in the Step-By-Step Book about Seahorses:

"Aquarists unwittingly cause a different sort of problem when they introduce copepods such as Cyclops to the aquarium while feeding live foods. These minute crustaceans reproduce at a fantastic rate (over a year’s time, the descendents from a single female may number over 4 billion) and can quickly transform your aquarium into a copepod soup. When your seahorses try to breathe this copepod-infested water, their gill tufts can become hopelessly clogged by tangled masses of the tiny creatures, resulting in suffocation. As the respiration becomes increasingly labored, the seahorses will signal their distress by panting for breath and going through a series of color changes.

"This problem is easily diagnosed by the cloudy or hazy appearance of the water. It can be treated by running a bedtime filter continuously for several days, while adding three drops of methylene blue per gallon of water. The diatom filter physically removes the copepods, while the methylene blue further reduces their numbers and aides the seahorses breathing. A complete water change is then called for…" [Giwojna, 61-62]

Nowadays, of course, hobbyists are all very conscious of the benefits copepods can provide as a highly nutritious natural food source for seahorses. As a result, seahorse keepers will often take special pains to establish harpacticoid copepods in their tanks or to culture them in great numbers for their seahorse fry, and on rightly so; in the 21st century, we are bombarded with articles extolling the many virtues of ‘pods to the point that few aquarists realize anymore that not all copepods are beneficial.

But that has not always been the case. Not too long ago, the aquarium literature was rife with references regarding "copepod pollution" in the fish tank and warnings about "copepod contamination" of the aquarium. In those days, the scientific journals included papers on topics such as "Should We Love or Hate Cyclops" and "Damage to Fish Fry by Cyclopoid Copepods" by Charles C. Davis (Ohio Journal of Science, vol. 59, pp. 101-102, 1959) and similar studies by the Czechoslovakian investigators Babak (1913) and Oliva and Sladecek ( 1950) describing attacks by Cyclops copepods on Axolotl fry. As an example, Davis points out in his paper that, "There Is clear and incontrovertible proof in the scientific biological literature that some of the species of Cyclops are predators… All Cyclops, whether vegetarian or carnivorous, have biting mouthparts, and in most of them the jaws are adequately powerful to cause significant damage to small fry." Suffice it to say there are countless species of copepods, a number of which are parasitic and a few of which are predatory, and even the harmless varieties can present problems on rare occasions when their numbers get out of control.

For instance, this is what Mildred Bellamy has to say regarding copepods in her famous book Encyclopedia of Seahorses:

"Although nonparasitic themselves, some copepods may still contribute to the death of fishes maintained in close-system aquaria by affecting respiration adversely. This condition is brought about by clogging of the gills or, in the case of the seahorse, the gill tufts, to a point were actual suffocation occurs in the fish involved. Copepods are prolific individuals indeed and, in the closed-system Celeste aquarium particularly, they may reproduce so rapidly as to almost stagger the observer who dips a sampling of water from the aquarium and examines it microscopically.

"In the wild, any freshwater pond will afford millions of [copepod] specimens of the genus Cyclops. The sea contain species of the same genus in such numbers that they, with allied genera, form a large part of the food of many fishes — even some species of whales find in them an abundant food supply. The reproductive powers of Cyclops are so great it has been estimated that the descendents of one female may number 4,500,000,000 individuals in a single year.

"Thus, uncontrolled in the aquarium, it is not difficult to envision how the water, swarming with these minute crustaceans, can become literally a nursery and that the mere circulation of such polluted water over the gill puffs of seahorses can be responsible for depositing thereon life-threatening masses of copepods.

"The gill tufts of seahorses living in water abounding in copepods will be found to contain "mounds" of the small creatures, those underneath voluntarily clinging to or crushed against the tender tuft tissue, with more and more individuals deposited on the initial layers. Then, as additional copepods are drawn into the tufts with the water circulated for the seahorse’s oxygenation, the copepods antennae, tail appendages, leg and body filaments become hopelessly entangled. Unable to move, the copepods continue to pile up until their bodies completely choke the vital area. Suffocation of the involved fish is inevitable.

"In the closed-system aquarium, the first warning of copepod contamination appears as smoke in the water; that is, the aquarium water looks as though it had smoke evenly diffused through it. Progression of this type of pollution causes the water to become smokier and smokier and finally, to assume a clouded yellowish or brownish tinge. Fish maintained in this kind of water often "pant" for breath and frequently go through a series of varied and variable color changes.

"… So much emphasis has been placed on the value of Cyclops as food for young fish that it may be possible their deleterious effect on some larger fishes has been overlooked…

"Although I have proposed that seahorses may become parasitized by way of the food chain and that aquarium water may become copepod-polluted, I want to emphasize here that I’m not recommending the discontinuance of live food. To the contrary, as I’ve stated elsewhere, seahorses require living food and will not long survive if they are deprived of it.

"On numerous occasions when Cyclopoid copepods have become established in my aquarium, I have tried almost everything in the book to reduce their numbers without harming the fish inmates, but I have yet to discover a satisfactory method for getting rid of the so-called innocuous yet devastating pests. In experimental containers, they have survived in water heated to 95°F, or cooled to 44°F. Hardy individuals, although slowed down considerably, have survived in water cooled to 39°F. Although some die, great numbers will live in water without artificial aeration much longer than most species of marine fishes will tolerate the condition. As far as chemicals are concerned, the dosage required for effective eradication usually will kill the fish long before the helpless-looking copepods succumb. A power filter is of slight value. A complete change of the aquarium water is perhaps the most helpful, but this is not a cure. I have tried dipping the fish up and down, literally "bathing" each individual, through several changes of clean saltwater in plastic pails or auxiliary aquaria set up for the purpose, wiping body surfaces gently with a soft wet cloth or sponge, and using wet cotton-tipped Q-sticks around the vents, gill chambers, etc. to rid all areas of accidentally or purposely clinging organisms before returning the fish to their home aquarium, the latter having been cleaned thoroughly and refilled with AIDS, filtered seawater that was free of copepods. Sometimes, within as little as two weeks’ time, incalculable numbers of the odd oar-footed creatures would be seen swarming in the recently cleaned aquarium, quite as thick as before.

"Methylene blue, three drops per gallon of water, does seem to help some. The water clears and the copepods appear reduced in number three or four days after the treatment but this, too, is no cure. The copepod population begins to build up again and unchecked, reaches nearly astronomical proportions in an unbelievably short time." (Bellomy, 181-183; when 86-187).

So that’s what you’re up against when cyclopoid copepods explode in a closed-system aquarium, Haynes. However, I don’t believe that’s what is happening in your case, sir. Cyclops copepods are very difficult to see with the naked eye, so if you have no trouble observing the individual white bugs, then they are almost certainly not Cyclops. And if the white bugs are confined mainly to the substrate and aquarium glass or decorations, rather than appearing like a smoky haze in the water column, then it’s safe to say that you’re not dealing with a copepod bloom. Cyclopoida copepods would also be interfering with your seahorses breathing, and as long as your seahorses are breathing normally, I don’t think I need to be concerned about the white bugs you noticed this morning.

Let me stress once again that you should not be overly alarmed by the appearance of these white bugs your tank recently experienced. Copepods in general are very beneficial and desirable in the aquarium, and potentially dangerous copepods blooms are really exceedingly rare occurrences. The odds are great that your white bugs are harmless ‘pods that are nothing to be concerned about.

In your case, Haynes, the breathing of your seahorses will be the best indication that your population of these white bugs has reached potentially harmful proportions. As long as the seahorses are breathing normally, all is well. What your seahorses closely to see if they are feeding on the white bugs. As long as they are not free swimming pods that can clog up your seahorses gills if they become too numerous and your seahorses are showing no signs of respiratory distress, everything is fine.

But if your seahorses begin to show signs of huffing, labored breathing, or respiratory distress, then it’s time to eliminate the pesky ‘pods. Or if you just want to play it safe and eliminate the bugs, that’s okay too.

If the bugs are free swimming or suspended in the water column, then micron filtration such as that provided by a Diatom filter may help, as recommended in my old step-by-step book, but if the bugs are really numerous, the filter media may clog frequently and you need to be prepared to recharge the diatom powder frequently until the aquarium clears.

If the white bugs are not free swimming but rather are crawling on the glass or the substrate, then a better option is to treat the aquarium with Parinox, or any other aquarium medication containing Dylox as an active ingredient, after first removing any sensitive invertebrates such as the shrimp or micro-hermit crabs or micro-starfish from your cleanup crew.


USE: For Ich, hexamita, costia, ichthyophthirius, ectoparasites, monogenia, hirudinea, parasitic copepods, argulus, lernaea, anchor worms, fish lice, leeches. Also a protozoacide. Anti-bacterial, anti-parasitic, very wide spectrum..

DOSAGE: Use 1/4 teaspoon per 20 gallons. Treat once a week for 2 weeks. If water changes are done, add back the percentage of medication according to how much water was changed.

As you can see, Parinox is effective against all of the ectoparasites and protozoan parasites that attack the gills of fish and cause respiratory distress. It should certainly eradicate your little white bugs, if that proves necessary. Although Parinox is safe for seahorses, it can be hard on crustaceans and certain invertebrates, so be sure to remove any invertebrates during the treatment. After the two-week treatment, perform a major water change and use activated carbon filtration or a Poly-Filter pads to pull out any remaining traces of the medication.

You can obtain Parinox online from National Fish Pharmaceuticals at the following URL:

Click here: Fish Medications

You can also try administering a mild dose of methylene blue (i.e., three drops per gallon) as suggested by Mildred Bellomy, but be very careful not to overdo it. You need to be aware that methylene blue will stain silicone permanently and can adversely impact your biofiltration at a stronger dose.

Most likely the white bugs are completely benign and will eventually disappear on their own, Haynes, as the seahorses feed on them and deplete their population or as the conditions in your aquarium change as it matures. My best advice would be just to watch them for now to make sure they don’t cause a problem. See if your seahorses are actually eating them, observe their breathing carefully, and watch to see if the white bugs begin crawling on your seahorses rather than the aquarium glass or substrate.

Best of luck with your new seahorses, Haynes. Here’s hoping you get all the "bugs" worked out of your new seahorse setup soon!

Pete Giwojna

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