Our female zebra danio has had some problems recently. Here are the required details:
1. What is the size of your tank? 140 L
2. What are your water parameters? State the brand of test kit used.
We use the API Master Testkit.
3. Is your aquarium set up freshwater or brackish water?
4. How long the aquarium has been set up?
The aquarium has been set up for almost 1.5 years
5. What fish do you have? How many are in your tank? How big are they? How long have you had them?
2 danios (male almost 1.5 years, about 4cm (= 1.6 inches) + tail; and female 1 month, about 3cm (= 1.2") + tail), 2 corydoras (both females almost 1.5 years and about 3.5 cm (= 1.4") + tail) and two Oto Cincluses (male and female about 8 months, male is about 2.5 cm (= 1") and female 3.5 cm (= 1.4")) - Those times are how long we've had them.
6. Were the fish placed under quarantine period (minus the first batch from the point wherein the tank is ready to accommodate the inhabitants)?
The new female zebra danio was not in quarantine prior to putting in the tank.
7. What temperature is the tank water currently?
26.5 Celsius (= 79.7 F)
8. Are there live plants in the aquarium?
There are two live plants that have been there almost a year.
9. What filter are you using? State brand, maintenance routine and power capacity.
We have an Eheim Aquaball 2210 filter. We clean the pads in tank water during water change once a week. 550 L per hour (=145 US Gallons per hour).
10. Any other equipment used (aside from heater and filter which are two very important components of the tank)?
No other equipment
11. Does your aquarium receive natural sunlight at any given part of the day? What is your lighting schedule (assuming you do not rely on sunlight for our viewing pleasure)?
The tank rarely gets natural sunlight, but if we let some sunlight, it's in the morning. Usually we keep the curtain so that the tank doesn't get sunlight. Automated lighting in the tank is on from 11.30am to 9.30pm. We live in Finland so at this time of the year there is no dark time of the night, hence the late time for turning the light on. It gets a little dim after about 10.30pm for a few hours, but still the same as on a cloudy day. During wintertime the light's on from 9am to 9.15pm.
12. When did you perform your last water change and how much water was changed? How often do you change your water? Do you vacuum the substrate?
Last water change was a 7 days ago and it was big one of about 50% as I took most of the gravel out and am meaning to rinse it in the next tank water that comes out as it seems very dusty regardless of cleaning. The following day i.e. 6 days ago I took under 10% water to hoover the gravel on the bottom. We have not done this before so it's not part of a usual cleaning process. There's still a little gravel in the tank and I will put the gravel back in little bits at a time after soaking it in tank water separately and hoovering it properly.
Our normal water change is about 30% once a week with a gravel hoover at the same time. The filter is cleaned in the tank water every time.
13. What foods do you provide your fish? What is the feeding schedule?
Our fish get meals at 9am and 9pm. They get flake and granule foods and pellets for the bottom feeders. Every two days in the morning they get either frozen white mosquito larvae or blood worm instead of dry food. We also put a slice of zucchini or cucumber for the otos once a day.
14. What unusual signs have you observed in your fish?
A few days ago our female zebra danio had originally a protruding butt. It looked possibly a little bit pink, but I thought first maybe because of the lighting, but it's gone away now. Also the protruding of the butt went mostly away, but the fish has two "lumps", the first one is the belly, then a thin bit and then another lumpy part to the body right above where the protruding was before. It looks like the fish has now lost weight apart from these two lumpy parts. The same lumpy parts are on both sides of the body. So this fish has only been one month in the tank. She eats normally, swims normally and doesn't show any other signs than mentioned above. Her friend died a week ago from what was thought to be internal bacteria. No treatment was put in the main tank, but she was in a hospital tank.
15. Have you treated your fish ahead of diagnosis? If so, what treatments did you use? State your reasons for planning ahead of proper diagnosis.
The tank was put some EasyLife Excital to treat a mild case of blue green algae two weeks ago. The treatment was repeated a week ago during waterchange.
Here are a few photos of the female zebra danio.