Sick Knight Goby

[Rainw]

My Knight Goby is always swimming around and seemed hyper and happy. This morning, he was lying on a leaf. I opened the top and he went to hide in his cave. He was against the wall at an angle. I shown a light on him and he swam away from the wall fine, but then swam back to it. I checked the temperature and turned off the light to cool it down. Now he's in complete hiding and I haven't seen him in more than an hour. Please help.

Tank size: 5 Gallons (alone)
Tank Temp: 29.5 degrees
Fish Symptoms: He looks perfectly healthy except he is not swimming around and his spots are dim.
Volume and Frequency of water changes: 15% per week
Chemical Additives or Media in your tank: Aquarium salt
Tank inhabitants: None
Recent additions to your tank (living or decoration): None
Tank Age (How long the tank has been up and running): September 11
Recent Events in the tank: None
The type and size of your filtration: Aqueon 5-15G

 

[WILDER]

The tanks to small for him.

I think they also need to be in brackish tanks.

What are your water stats in ammonia, nitrite, nitrate, and ph.
What do you feed the fish.
Does he look bloated.
Can he maintain balance in the water.

 

[Ceramicbull]

My Knight Goby is always swimming around and seemed hyper and happy. This morning, he was lying on a leaf. I opened the top and he went to hide in his cave. He was against the wall at an angle. I shown a light on him and he swam away from the wall fine, but then swam back to it. I checked the temperature and turned off the light to cool it down. Now he's in complete hiding and I haven't seen him in more than an hour. Please help.

Tank size: 5 Gallons (alone)
Tank Temp: 29.5 degrees
Fish Symptoms: He looks perfectly healthy except he is not swimming around and his spots are dim.
Volume and Frequency of water changes: 15% per week
Chemical Additives or Media in your tank: Aquarium salt
Tank inhabitants: None
Recent additions to your tank (living or decoration): None
Tank Age (How long the tank has been up and running): September 11
Recent Events in the tank: None
The type and size of your filtration: Aqueon 5-15G

Knight gobies can be kept in fresh water, but brackish is generally better since it reduces the chance it may get sick (it doesn't take much salt). I'm sure it appreciates the aquarium salt, but if I were you I'd change to marine salt, and just add enough to get to 1.002-1.005 SG. Otherwise, none of the behavior you are describing is honestly all that odd for a goby. They spend quite a bit of time just chilling on a leaf or the side of the tank. Make sure you keep the temp at standard tropical temps, 29.5C is far too high, aim for 20-26. Honestly, I'd be a bit more concerned about the "hyper and happy" phase. Mine don't typically get all that excitable unless its mating time. I'd also say that it would be best to put him in a bigger tank.

EDIT: I just re-read that and I might be misunderstanding. When you say "against the wall at an angle" do you mean attached to the wall by his suction cup fins or leaning against the wall on his side?

Also, if you can't find him at all, look around the tank, they do jump. If you don't have a lid he may be outside the tank.

 

[Rainw]

Thank you all for your replies!

I'm moving him to a 10 Gallon next week. I originally got him for my community tank, but he attacked my Glass Catfish, so I moved him to the only tank that was ready for a fish.

The ammonia, nitrite, and nitrate are good, but the water is soft. My tap water is well water.

I alternate between New Spectrum Small fish pellets and Mysis Shrimp. (Shrimp on MWF) I tried giving him bloodworms, but he doesn't care for it (I'm almost positive this is weird).

I don't think he looks bloated, but he's my first Knight Goby. I have videos of him when he was healthy on YouTube (My channel is BloodRainW).

I can't tell if he can remain balance because he's hiding in his cave, but he normally can.

I did get the temperature down, but only by three degrees.

I've followed the instructions for the aquarium salt, is it okay to add marine salt to it?

He was against the wall on his side, as if he were having trouble staying down, but when I shone the light on him, he swam away a little as if he were fine. The he went back to it when I took away the light.

I know they jump, because the petstore had one between the wall and tank. I have a secure lid, and have spotted him this morning, sitting on the bottom of his tank. I had to go to work, so I’m worried about what I’ll come home to. I didn’t know the hyper Goby was unusual. He was hiding all Sunday as well.

 

[Ceramicbull]

He just sounds stressed from the water chemistry and tired to me. Add marine salt and get him in the 10G as soon as you can. (see below) What is the pH? They generally like the pH to be fairly basic. If it's soft I'm afraid it might be way too acidic.

No bloodworm? Wow, that IS weird. Every fish I've owned so far goes absolutely gaga for the stuff (except for my vegetarian male molly). Most of the time my knights spend camping out somewhere, usually perched on something high or the tank wall, just keeping an eye out for things (always hoping a small fish will somehow show up). Judging by your videos, first of all, he is a she. Second, she's occasionally doing the corner dance, which means she's swimming up and down at the corner and something is wrong with the water (or she is bored) and she wants to get out to different water. I'm guessing this is the softness and the temperature (and possibly the size). If that's the current setup in the video, everything else looks fantastic, she looks healthy and fit. If those are live plants, however, the salt may kill them. Here is a list of brackish adaptable plants. The food sounds fine, although you don't really NEED the pellets, flake should work fine if you have it. But when you feed mysis, do you feed an entire cube?

Marine salt will help you with the softness (and pH if that's an issue), and you really don't need much. It should also help with a lot of potential diseases that might be bugging her. Buy a hydrometer if you can, and just add enough to get the water to somewhere between 1.000 and 1.005, about 3 heaping tablespoons<->1/4th cup. You don't have to always hit the same point, in nature they're constantly moving in and out of different water masses with different pH, salinity, temp, etc. Just add it to the fresh water when you're changing it, let it dissolve, and then add it to the tank (undissolved salt + fish is risky). Once that's done, you've completed the hardest part of brackish fishkeeping. The 10G will make it easier to keep the temp where you want it.

You could try a tankmate to liven things up after you move her and cycle. Perhaps another knight goby, male or female doesn't terribly matter, although with a male you might get to see them do some mating habits. The fry are nearly microscopic, and next to impossible to raise. I'm kind of surprised she attacked the ghost cats, generally (unless it can be eaten,) they only attack fish that stray into their territory; and that territory is usually pretty small. Typically, in that case, the "attack" is just a peck to remind the trespasser where they are.

So long as it doesn't look like velvet, the only thing I can think of that space and salt won't cure might be internal parasites. Is her poop mucusy and/or stringy?

Good luck, and let us know how it goes, please.

 

[Rainw]

Thank you for telling me she’s a female. I should probably change her name.

I bought a Hydrometer, a box of Marine Salt (Instant Ocean). I put the salt in both the 10G and her current 5G tank. She seems to be getting better.
She was out of her cave for a few hours today, and swam fine, but now she’s back in hiding. She sat on her log and watched me for a long time. She doesn’t seem to have any trouble swimming, but she did sit on the gravel for a while. I think she was messing with me, though, because every time I looked back at her, she was motionless, but had moved half an inch. When I put the salt water in, she came out to check things out, ate, swam a little, sat on her log, and went back into hiding.

She’s not going up and down anymore in the corners, so I guess that’s good, but is it okay for her to be in hiding so much? Is there a way to make her less skittish, like adding another Knight Goby?

I was able to get the tank down to 25 degrees.

I haven’t seen her poop.

Will two Knights fit in a 10 gallon without territorial problems? And how can I tell the difference between a male and female? Online, it says males have longer fins, but I can’t tell. The pet store just got two new Knight Gobies in; one has blue on its dorsal fin.

Is it better to get another female, or to get a male?

Thank you for the replies.

 

[Ceramicbull]

I hope this helps with gender:
These are both male. Link 1 Link 2 Note how the body is slender, and the 2nd dorsal and anal fins are longer and square off more than the female. Here is a pic of a female, she has a more pronounced belly (full of eggs, they look a lot thinner after mating) and her 2nd dorsal and anal fins are shorter and rounder. When the male goes into mating mode, it will become very clear as the edges of his fins will tint black. I hope that helps.

I just thought about it, and all gobies do tend to burrow a bit. If you do get a male, he is likely to try to excavate a den for mating purposes. I don't know if its worth it to you (you've spent quite a bit on one fish already,) but sand rather than gravel might help. I'm happy that it seems clear that the fish is in no mortal danger. Her behavior might just be natural, mine do spend quite a bit of time hiding. Mine are also fairly skittish, but time will help. Mine eventually realized I was the source of food (took over a month), and would always be glad to see me walk up to the tank. Are there any sources of irritation nearby? Slamming doors? Speakers? That might be irritating her into hiding.

She may just be hiding because nothing interesting is happening in the tank, so adding another fish might make life more interesting. I'm rather hesitant to say one way or the other there being enough territory to split in a 10g, particularly if yours has a mean streak. Make sure both have a place to hide, add both to the tank at the same time if you can and rearrange the scenery to break up territories. As far as which combination would be best, I suspect that male/female might be less likely to have aggression, as there are valid reasons to be in close proximity. It would be a safer bet in 20g, but you already set up a 10g tank just for her.

If you're worried about territory issues, a set of 3 mollies (1 m, 2f; or all females if you don't want any fry) might be easier tankmates, they can live in both brackish and fresh equally well. That means if there is a problem you can move them to the community tank... or the 5g. They also are peaceful (with other fish), occupy the upper tier of water (rather than the knight's mid-bottom), are entertaining to watch, and will provide a constant stream of free live food for your knight goby (the fry). So long as they're large enough when you add them (knight gobies are famous for eating anything that they can fit in their mouth and ignoring all else), the adults should get along just fine with her.

 

[Rainw]

Her tank was actually right next to the door, but my bedroom "door" is a curtain.

The problem with a 20 Gallon is that my floor is very weak. I can't put tanks in the rest of the house because I can't control the temperature well enough. I have to spread smaller tanks out, and that limits the kind of fish I can have.

The fish store had three Knights. One was probably a female, and one was a male but massive. I got the medium one, which I think is a male. Both ones I think were male had slight fin damage, mostly on the dorsal fin. I put both Knight Gobies in the 10 Gallon. After a half an hour, I turned on the room light, then another half an hour, I turned on the aquarium light and left them alone for a few minutes. They're both swimming around. I think they're exploring. I put in a "shelf" decoration for them to sit on. They seem fine unless they get close. The "male?" has snapped at Templar (the female), and they've circled each other. One time, they opened their mouths at each other. Is this okay? Are they fighting? Are they going to hurt each other or get over it?

 

[Ceramicbull]

It just sounds like they're establishing territories, or even possibly sizing each other up for mating. Nothing you've said so far rings any alarm bells. When my male decides it is time to mate, he'll act semi-aggressive to the female, circling around her (sometimes very rapidly), and applying mild bites. Eventually this somehow convinces the female to lay eggs. After you watch it a couple of times its just funny, really. If they were really fighting, there'd be no letup in the chasing and biting. When a territorial fish fights, it will pursue until the weaker fish was driven from the stronger fish's territory. If there is a fatality, this usually means that the territory encompasses the entire tank. So long as the pursuit is not constant, or if eggs are produced, then they ought to be fine. Typically they don't fin-nip or any other aggressive behavior.

If they do lay eggs, be prepared to clean your filter.