discovered unknown "jumpers" on top of the water

[DamianWarS]

I have recently discovered some things that are living on top of the water of my tank. They are smaller than a pin head and they constantly jump. At first I thought it must be some floating debris but upon closely looking at them they are in fact living creatures. They keep away from the flow of the filter and are the same colour of fish flakes. I tried to get a picture but they are too small and too fast to get a focus on. They do not go under the water but only float on top of the water. Does anyone know what these things are and if they are harmful to my tank?

[Northernguy]

Welcome to the wonderful AC!
Thats one I havent heard of but if its a bug your fish will probably enjoy them!
Are you doing your water changes?
How big is your tank?
What kind of filtration?
What kind of fish and how many?

[DamianWarS]

I do weekly 25% water changes. Ammonia is at 0 and ph 7. I don't have a large collection of fish just 6 neons and 3 Serpae Tetras. I have a planted tank and a piece of malaysian driftwood. The filter is a Power Filter meant for a 30-40 gallon tank. My fish don't go to the water line too often so it seems their presence is unknown by the fish for now.

[Northernguy]

Here is a link that may help with taking pics. Not sure whats happening in your tank though:http://www.stopactionphoto.net/Photoprimer.html

[DamianWarS]

it took a while but i caught one with my ph testing tube. its hard to get good pictures because they are so small but at least they are still in the testing tube. all i can really see is that its a bug.

[smaug]

Dave66
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They are mites. They are feeding on the biomatter on the surface scum of the tank. Most foods have fish oil or similar as an ingredient, and that oil settles on the surface, bacteria start work on it and the mites show up to take advantage of the bounty.
You can clear the oil with a clean sheet of paper by dragging it smoothly across the top of the water. May take you a couple sheets get rid of all the scum. No scum = no mites.

Dave

The above was taken from a thread I started a wile back.They are harmless,and they give you an excuse to buy a few hatchet fish,they love these things.That is of course if they are appropriate for your tank.

[DamianWarS]

thanks that makes a lot of sense because just recently i have noticed an oil scum on the surface of the water. when you look at it from certain angles you can see its all multicolour and when you touch the water all the scum separates and moves away from your finger. i didn't think the bugs themselves were harmful I was more concern with what changed to support them coming.

can the oil scum be a hazard at all? or is there a type of food I can get that won't contribute to the scum as much? In any event I might try the paper towel method to get rid of the scum. I'm not sure about the hatchet fish, i would be too afraid they would jump out of my tank. I have a lid but I thought those fish are pretty jumping aggressive and i would be worried they would jump out of the cut out holes for the filter or when i clean the tank.

[Dave66]

It can be a problem, Damian, if the water surface isn't broken by filter outflow or air stone. The oil interferes with the gas exchange at the surface of the water, and a thick layer can actually suffocate fish.
The hatchets jump usually after sudden lights out in the evenings. You can use nylon screening over the open spaces in your hood to prevent it. They won't jump out when you clean your tank; they will take cover in a back corner from fear.

Dave

[smaug]

It can be a problem, Damian, if the water surface isn't broken by filter outflow or air stone. The oil interferes with the gas exchange at the surface of the water, and a thick layer can actually suffocate fish.
The hatchets jump usually after sudden lights out in the evenings. You can use nylon screening over the open spaces in your hood to prevent it. They won't jump out when you clean your tank; they will take cover in a back corner from fear.

Dave
I lost dozens of marbled hatchet through tiny quarter size Clarence holes in my accessory strip.They are masters of jumping through hoops..
For the poster:Do you have any floating plants at all?That is where my mites came in from and where they took refuge.I never had that bio film but a thick mat of dwarf water lettuce.

[Northernguy]

Good point smaug! I new the oily residue could suffocate the tank,I had no idea that floating plants could get thick enough to do that. I thought that they only blocked light.
Thanks :19:

[smaug]

Good point smaug! I new the oily residue could suffocate the tank,I had no idea that floating plants could get thick enough to do that. I thought that they only blocked light.
Thanks :19:
No,I wasnt saying that floaters are harmful to dissolved 02,just that they can bring in and harbor these mites.Sorry for the confusion.

[Northernguy]

Are the mites fish food?
Can the mites hurt the fry?
I had no idea about these.I have had the oily residue but its gone.I have never seen any mites(thank god).
I do have a lot of floating plants so I just want to about these,just in case.
Thanks

[Dave66]

If the mites are visible to the fish they'll eat them. I get similar mites with my white, Grindal and red worm cultures. Harmless, and good fish food.
The mites don't attack any fish, including fry.

Dave

[DamianWarS]

smaug i don't have any floating plants and the plants i do have i have had for a long time. i don't know where they came from but im not worried about the mites The oil scum is something i will do something about however. thanks for all the posts!

[Fishalicious]

I have had something like this before as well.... I discovered that they came with my floating plants... in my case they were Podura aquatica a type of Collembola which is why they like to jump around so much...

Only fish I know to snack on them are labyrinth fish but not enough to erradicate them. They eat specks of floating detritus, algal cells, fungal spores & the lipoproteins of the surface film itself - they also lower nitrates :19: So other than looking unsightly they are not really a bad thing and completely harmless :c2:

http://sparkleberrysprings.com/v-web/b2/images/s/pondspringtails121906h.jpg

[Northernguy]

Good to know! Thanks:19:

[smaug]

I have had something like this before as well.... I discovered that they came with my floating plants... in my case they were Podura aquatica a type of Collembola which is why they like to jump around so much...

Only fish I know to snack on them are labyrinth fish but not enough to erradicate them. They eat specks of floating detritus, algal cells, fungal spores & the lipoproteins of the surface film itself - they also lower nitrates :19: So other than looking unsightly they are not really a bad thing and completely harmless :c2:

http://sparkleberrysprings.com/v-web/b2/images/s/pondspringtails121906h.jpg
Hatchets eat them like popcorn.