Fish Crazy
Feb 21, 2017
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Hi I'm new to this forums and forums and general, so I really don't know if I'm posting on the right thing or anything, but my fish have been flashing ever since I put them into a new tank, I don't know if it needs cycling, because my beneficial bacteria colonies have already grown on my filter grid, and drift wood. Everyone's flashing, the Pygmy cories, my neons and one cardinal and even my Betta! I'm afraid o don't have access to any testing kits besides my PH testing kit, which reads about 6.8 (high for tetras) but still I don't think that would bring on flashing as their usual ph was around 6.0-6.5 something seems fishy here
Flashing means irritation to the skin. It could be from parasites, off water parameters or a skin infection. Are there any physical injuries like scratches, split fins, lumps or bumps on the fish? Could you upload a few pics of the fish that are flashing?

The first thing I would do is a 50% water change. When it comes to fish, when it doubt do a water change. If the ammonia or nitrites are high then the water change will help, and it won't hurt even if the parameters are stable.

How old is the tank and what size is it? What temp do you keep it at? Other than the fish you listed, are there any others?

I know it's a lot of questions but the more we know the better we can help
Hi, and thanks for replying, I doubt it's parasites, the Pygmy cories did carry parasites and it spread to the other fish in the old tank, however that issue was completely wiped out, as I killed what was most likely a Gill fluke outbreak, the tank is 10 gallons and has been set up for about a week, the filter Cartriages and driftwood already contain an established colony of denitrifying bacteria. The relative temp is 78-80 degrees and the fish are two veil tail Bettas (female) peppered corydoras (temporary) a juvenile male and female bristle nose pleco (temporary) 3 neon tetras, one cardinal tetra, and two Pygmy cories, plants are: crypt parava, Amazon swords and Argentine swords, the b I siphon the sand bed daily as of now, and their is no hydrogen sulfide build up in the substrate, the tank has no foul odor Nor is the water cloudy either, what is strange is my other female Betta does not flash, neither my pelcos
the tank is 10 gallons and has been set up for about a week,

The proper way to set up an aquarium is to put water and ammonia in it to get the ammonia and nitrite consuming banter growing. It normally take 2 to 4 weeks for this to happen. Only Then do you add fish. Please read the following.:http://www.fishforums.net/threads/cycling-your-new-fresh-water-tank-read-this-first.421488/

You claim the filter has an established colony of bacteria. However without a test kit for ammonia and nitrate there is no way to know if you have a colony of bacteria. Do a daily water change of at least 50%. And get a text kit as soon as possible. Only when you can confirm that you have no ammonia and nitrite can you stop doing daily water changes. However continue testing the water daily for ammonia and nitrite. If the levels come back do an immediate water change. Ammonia and nitrite should both read zero. Anything above her means your tank is not cycled.
Well yes my filter already had a pre established colony, from the last tank,
I did test it and my cycle was compete , I simply moved the filter to a new tank. Does it have to be recycled? The filter, filters is 5-10 gallons
I simply moved the filter to a new tank. Does it have to be recycled? The filter, filters is 5-10 gallons

Not only is it an issue of if there are bacteria in the filter. Do you know if there are enough bacteria in the filter. Ntirogen consumming bacteria don't just live in the filter. They live everywhere in the tank. And if conditions are not quite right most will live outside the filter. So sometimes it may be necessary to recycle a tank even if the filter is established. If that is the case then sometimes the new tank will cycle very quickly. The only way to know is to test the water for ammonia and nitrite.
Actually, I think I new what was causing the flashing in the tetras, they came down with neon tetra disease, I looked it up online and many had white tattered areas on there fins and slight discoloration. I euthanized the tetras, in a clove oil solution this morning, as for the other fish flashing I'm sure it's a water perameter issue. It's says neon tetra disease is spreadable to other fish though.. I'm really confused at this point
I have been feeding live foods lately so maybe it was a carrier for the disease
The flashing occurring by all the fish, or more than just one neon tetra, signals that whatever is causing it, all the fish are being affected.

It is unlikely to be neon tetra disease; many jump to this conclusion, but while it could be, the cause is probably much closer to home.

Not being able to test your water is severely hindering any help we can give you. A test like the API liquid Master Combo (pH, ammonia, nitrite and nitrate) is well worth the cost. Or at the very least, take a jar of tank water to a reliable fish store and ask them to test it for ammonia and nitrite. Make sure they give you a number, not some vague useless term like (a bit high" or "acceptable." If we do not know the actual number for ammonia and nitrite, we are only guessing.

The other thing is that ich (white spot) is very common, and this always begins with flashing because the parasite first attacks fish in the gills where it is unseen. This is now believed to live permanently in many aquaria, but only cause an outbreak if fish are stressed, as they would be in a new tank, being netted and moved, etc. A new tank is not established, even if it is cycled, and this can cause stress to many fish, esp cardinals.

Photos (provided they are clear) would help, if there are external signs. I am only guessing, but I would suggest this is either a cycling issue or ich, or both. Ammonia or nitrite above zero will both cause flashing, and that means stress, which may bring on ich. Fin degeneration is also a symptom frequently seen with ammonia or nitrite poisoning and ich. You have to assume it could be several issues, and eliminate them one at a time. Water tests are always a first step, and a major water change will never be detrimental at the first sign of such symptoms.

how do I post pictures?

At the bottom of the window when adding a post there is a box "Upload a File." Click on that, and you can download digital photos from your computer. This is how I do it. Others somehow do phone photos (no idea how),or use photobucket (no idea how to do that either).

This will be useful if there are external signs on a fish.
The pictures


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The cardinal acts like a Cardinal, it's Constantly foraging, it's colors are bright and it's belly looks full it shows no sigh. Of slowing down, but it flashes about every 10 minutes with 30 seconds of consecutive flashing with every interval between each flash being 4 seconds, the Pygmy cories act like cories, they rest for about 5 mins and the they go foraging, they flash about twice an hour for about 10 seconds of consecutive flashing

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