what are these white worms in my fish tank?

Question

they seem to live in the gravel, they are small and look like tiny bloodworms although they are only maybe 5mm long and as thin as a hair.

when cleaning the gravel I can see them in the bucket of waste water and there must be thousands of them.

A small ammount can always be seen floating around in the water, which my gouramis seem to like eating.

however i want to know what they are and how to get rid of them. Any help apreciated.

just a few more details, the tank has live plants in it and is regularly cleaned.
emptying it and cleaning it out is not an option as it is a very large tank and to drain wash and refil the whole lot is going to be a very big job.

and i have seen my fish poop enough times to know thats not what it is!

Answer 1

Probably not a planaria, although these qualify as "white worms". These have a wider body like a slug, but are flat - they also have definite "eyes": http://www.notatall.blogger.com.br/planaria.jpg

These may actually be a relative of a bloodworm. Bloodworms and lighter colored relatives belong to the family Diptera (true flies) although the larvae are aquatic just like in mosquitos. The adults lay eggs on the water's surface or in the filter, and when they hatch, it looks like you have an infestation of small worms. "Bloodworms" just refers to any of the family where the larvae are red rather than whitish.

The could also be nematodes. These are small roundworms which are differentiated from other worms like earthowrms because they don't have segmented bodies (they're smooth rather than having "bands" around them). Although some nematodes can be parasites, if there's large enough for you to see them, they wouldn't be one of these types.

If you can see one under a microscope or very close up, you can also tell these apart because the fly larvae will have a definite head an a false "leg" right behind it (heads are at bottom in photo: http://www.benthos.org/Education/SlideLibrary/Shadows/035-Chironomidae.jpg ) where nematodes will just be pointed at the ends: http://www.jcw.org/edgames/edgamematchimages/BBFig.%20142%20Nematode.jpg Nematodes are a natural part of the aquarium and are a benefit since they help to break down wastes to smaller particles that the bacteria can decompose even more quickly (actually if you saw under a microscope all the things that live in the gravel and do this you might be surprised!). The nematodes will always be present in some number, and if what you have are fly larvae, these will eventually emerge as adults and leave on their own.

Your gouramis probably are enjoying the free food supply, as they would eat either type. If you do have them in large numbers, they must have a food source in the tank (generally organic matter built up in the gravel). You may need to vacuum your gravel with a siphon on a more regular basis or reduce the amount of food you feed your fish. If their food supply decreases, so will the number of your "worms".

Answer 2

This sounds like a case of Planaria. Planaria are flatworms, related to flukes and tapeworms. They are quite small, and if examined closely have eyespots as well as protrusions from the sides of their heads. Although they do not harm fish, they love to feast on eggs, and therefore are dangerous if breeding egglaying fish. Even though Planaria do not harm fish, they are an indicator that the aquarium has a problem. They require a food source, which means there must be excess food wastes in the tank to support them. If you have Planaria it's time to give your aquarium a thorough cleaning.
Pay particular attention to the substrate, as that's usually where they find their food. Make sure there are no dead plants, or other wastes in the tank. You should also take a hard look at how much you are feeding your fish. Usually the excess waste the Planaria are living on is the result of overfeeding your fish. Reduce the amount you feed your fish, as well as the frequency of feedings. Finally, once you've cleaned things up, be sure to continue with regular maintenance and water changes. A clean tank is the best defense against becoming overrun with Planaria.

Answer 3

Many of the answers posted her are a "best guess" scenario as it's impossible be certain what's infesting your tank without being able to see the problem. There are MANY possibilities with many variables affecting the correct diagnosis. The best thing to do is to make an inventory of all the variables regarding your tank such as substrate, type and number of fish, where fish were purchased, when were fish purchased, what food is fed, etc. Most important: Take a water sample that includes the worm/parasite and enough water to test. Take the notes and sample(s) to a reputable aquarium/fish store!! All good fish/aquarists will test your water and with adequate information they will be the best source of information regarding what is going on in your tank. The only way to get a good result is to SEE what's in your tank. Any diagnosis here is a guess because we can't see what's in your tank.

Answer 4

Sounds like they are Planaria, a type of flatworm. They don't hurt the fish but are a sign that the aquarium needs a good cleaning. Their presence also sometimes means that you are overfeeding your fish.

One way I saw recommended is to remove your fish from the tank and heat the water to about 95 degrees for a few hours, which should kill them. Another way is to use a commercially available fish tank dewormer.

To keep from getting them in the future it is important to make sure to keep the tank clean, and consider adding more filtration.

Answer 5

They sound like nematodes to me too.I've heard the reason they come out of the gravel is if you are cleaning it too much.When you clean out all of their food,they come out to look for something to eat.You only need to clean about 30%of your gavel every 2 to 4 weeks.If your cleaning more than this, it could be the reason your seeing them.If your not cleaning more than this,I have no idea.

Also its never a good idea to completely clean out a cycled tank.This will remove all of the good bacteria,start the whole cycle over again,and could kill your fish in the process.

Answer 6

not sure exactly what they may be, definately not blood worms. possibly hook worms or round worms. they are most likely parasitic. if they are in your gravel and your fish are eating them... i hate to say the only way to be 100% sure they go are to remove the fish and clean the tank. take out everything. do not buy any new fish. if the worms return. then your fish are infested also. you'll have to kill them or wait for them to die then clean the tank again. and start over. now if you dont want to be 100% then take a sample of the worms to your local pet store and see what kind of fishy drugs or wormicides they have you can dump in your tank. good luck

Answer 7

They are probably planarians. They aren't harmful to your fish. Sometimes they form in the tank due to over feeding. So...feed them only what they will eat, and clean out the tank.

Answer 8

Don't listen to the guy above me ^... Fish poop is not white. they have many different types of worms. you need to empty the whole tank. ensure none of your fish have them on there fins. got to the fish store and talk to them they will be able to break down which treatment to use. just in case bring a bit of the water and with you so they can see it. it is hard to tell without being able to see it.

Answer 9

I had this same problem. Here are some pictures of what I had. Do they look like this?
http://i140.photobucket.com/albums/r17/ConnieB247/DSC01443.jpg
http://i140.photobucket.com/albums/r17/ConnieB247/DSC01442.jpg
http://i140.photobucket.com/albums/r17/ConnieB247/DSC01242.jpg
http://i140.photobucket.com/albums/r17/ConnieB247/DSC01229.jpg

If so they are probably nematodes. I received some great advice here about these from Copperhead and it cleared my tank in a few weeks. I had to do lots of gravel cleaning and cut back on the feeding but it worked.

Answer 10

Take a sample to a pet store to be certain...anyone here is just guessing....baby fish, fish poop, worms if you have fed the fish worms, if you have live plants it could have come from them....theres lots of could be's...get it checked in person.