What is this? And ongoing problems...

[IndigoNight]

Hello!

My current problem is with one glo danio, but I've had ongoing issues (different ones) with many fish. I have no idea what's wrong with the danio, so that's my immediate concern, but also just want to figure out if I have an overall problem.

I'll try to answer all the questions in the sticky:

1~What type of fish is afflicted? In addition, please describe what is wrong with the fish to the best of your ability (i.e. cotton like growth, bloated, etc.).

Glo danio is looking terrible. No cotton-like growth, but he looks all misshapen from his... jaw?... to his middle, and a small piece of his tail is missing. And he's skinny. I'll attach a pic.

2~What are your tank parameters (ammonia, nitrites, nitrates, temp, pH)? Please give exact values.

Ammonia: 0, nitrites: 0, nitrates: 20, temp 75, pH 7.2. These numbers have been COMPLETELY consistent, every time, since the tank was cycled in June 2017.

3~ How large is the tank? How long has the tank been set up?
20 gallons since June 2017 (9 months)

4~What type of filtration are you using? Please give the name and number (i.e. Fluval 304) and amount of gph if known.
Marina Slim S20

5~How many fish are in the tank? What kinds of fish are they and what are their current sizes?
4 platys (3 adult, one juvenile)
6 glo danios (adult) and one 6-week-old fry
1 guppy


6~When is the last time you did a water change and vacuum the gravel? How often do you do this? How much water do you remove at a time?
Today. I do a 25% change every week and I vacuum the gravel.

7~How long have you had the fish? If the fish is new, how did you acclimate it/them?
Had this fish for about 6 months.

8~Have you added anything new to the tank--decor, new dechlorinator, new substrate, etc.?
no

9~What kind of food have you been feeding your fish, have you changed their diet recently?
Same as always: Spirulina 20 and very rarely freeze-dried brine shrimp

Here's the overall story:

I got the three platys first and cycled the tank with them in June 2017. They're all doing great. The only issue I had (recently) was that one platy had two flat white spots (not raised, not ich) on her tail, but that went away on its own.

Then I added three guppies in July 2017. The male died very quickly (within a week or so). One of the females is still alive, the other one died completely out of the blue maybe a month ago. She looked fine until I found her dead.

Then I added 5 danios from one pet shop around August 2017. Although I thought they looked fine when I bought them, over time I noticed some of them seeming to get skinnier/less "rounded" even though they were eating plenty and swimming around just fine. I added three danios from a different pet shop at some point. All three of the other pet shop's danios look completely different from the original ones... they're clearly much healthier, bigger, fatter, etc.

Finally, I added a honey gourami.

The honey gourami developed dropsy after about a month or two and died quickly. One of the original danios died unexpectedly the next day, no signs of dropsy.

So basically, I feel like I've had a few different problems and yet all the parameters look perfect every time and I'm trying really hard to get things right.

The only other problem I've had is that the diatoms will NOT go away. They started around October and persist six months later. I have taken decorations out and scrubbed them (just with my hands and water) and within 2 weeks they're brown again.

I have the lights on a timer currently on for 10 hours a day because more light is supposed to be good for diatoms. I also used PhosGuard for about a month to try to get rid of diatoms, but it did nothing.

The only other thing I can think of that could be a problem is that it's rarely completely dark in the room with the fish. It's my office and I work overnight hours, so even though their light is off, there's ambient room light for all but about 3 hours a night.

Limitations: I don't have a quarantine tank. My current heater is pre-set to 75 and can't be changed. I'd ideally like to get a quarantine tank, but I don't want to go through the expense of it if I can't get this tank stable, because this has become a really frustrating hobby!

I welcome any advice. Sorry this was so long.

 

[Kitekat87]

That doesn't look like a deformed jaw to me, more like it's belly is completely sunken in. My first thought would be some kind of internal parasite that is stopping your fish getting the nutrients they need to thrive.

Have you treated the tank with anything? I would recommend something like API General cure.

 

[WaterWalker01]

Morning, and welcome. Let's dive in. Dropsy is a symptom of many possible problems. It is not a disease on its own. One of them is parasites. And by the looks of the danio, I would think it could be the issue. Maybe someone who has knowledge can comment on meds to use.

Now, as to problem number 2. The diatoms. For more help on this, you'll need to say what changed 6 months ago when this started. But, generally brownish in color, they feed on excess silicates. (Guys with sand substrate like me will most often fight this fight). I will tell you what helped for me. Stronger water movement, larger filtration, a good size cleanup crew of about 50 neocaridina shrimp, and some proper SAE's.

And seeing as we got onto filtration, from a quick Internet search, your filter seems to be clear? If that is the case, I would recommend this be changed for one that is opaque to completely dark. The reason for this is that BB require absolutely zero light. They are very sensitive to light, and this can and will cause them to die off. (Think of mushrooms. They grow at night). As for the length of the post, the more info you can provide, the better chance of getting proper help.

WW