Fish rubbing himself against objects

[Sinuhe]

I have a brand new freshwater tank, 128 liters/ 33 gallons.
pH 7,8-8,0
Ammonia 0 ppm
Nitrites 0 ppm
GH 4 dH
KH 3 dH
Temperature 24C/ 75F

I have 2 Zebra Danios in the tank for cycling purposes, and I've only had them since yesterday. Now one of them has started rubbing himself against plants and other objects in the tank, as if he's itching. I don't see anything out of ordinary on the fish on the outside, and he's lively, and eats well. I know that rubbing against objects may be a sign of parasites, but could it also be the water that's irritating it, like the low hardness level? If it seems like it's a disease, I'd rather just get rid of the fish altogether rather than medicate the tank while it's cycling, or putting the other fish at risk of catching it. (I don't have a quarantine tank yet.)

I had a tank some years ago, and had the exact same problem. The fish looked fine on the outside, but kept rubbing themselves. I tried different types of medication, but it made no difference. I got very frustrated, and that was one of the main reasons I gave up on the tank finally. I don't want that same to happen again.

 

[Allivymar]

Does that fish appear to be breathing heavily or faster then the others? It may well be parasites, ich specifically. It can infest the gills first and not yet be visible on the body. I tend to think its more likely disease rather then water parameter based.

Also, if it is a parasite you'll need to treat both fish as it means the other will have it as well, although it may be subclinical and not an active case. But it would be able to infect new fish that are added later. As for cycling and medicating, you have barely started cycling if you just added the fish and did not do a fishless cycle previously, so I wouldn't worry to much about starting over. If the tank was previously cycled, move the danios to a QT tank and treat them there; if you leave the main tank fallow for a couple of weeks the parasites will not survive as they have no host.

Keep an eye on them for the next day or so, and see if they breathe heavily, start showing spots or the gills look swollen or unusual.

 

[Sinuhe]

Thanks for your response!

As far as I can tell, he's breathing normally.

I have a bad feeling this will turn into something as frustrating as with my previous tank. I'm probably just overreacting, but I just really wished to get a clean easy start for once .

 

[Allivymar]

LOL I hear ya. My guys have had ich, I've had infestations of snails, nematodes and hydra. Now I have some mysterious things living on my tank walls and plants. *shrug* I look at it as challenge. If I didn't I'd prob rip my hair out LOL

 

[Sinuhe]

I was wondering if I should add salt to the tank? I've been going to do that, anyway (for the platies that I'm planning to get eventually). I read that salt can help with gill parasites, which this could be. Based on the info I've found online, danios apparently can handle a bit of salt in the water. Do you think that would be a good idea?

 

[Allivymar]

Certainly won't hurt; danios are fine with some salt in the tank. I'd start with 1 tablespoon per 10g and see how that goes. If it appears to be helping somewhat, up it to 1 tbsp per 5g.

 

[Sinuhe]

I added 3 table spoons of salt yesterday, and another 3 just now (it's now 1 spoon per 5 gallons). (Before adding the second set of salt) the fish still kept rubbing himself occasionally, but most of the time he acts normal. He's lively, I still don't see anything abnormal on him on the outside, and he likes to chase the other, smaller danio around. Then, every once in a while, he gets a "fit", and rubs himself a few times on objects, to return to normal behaviour in less than 1 minute. And he eats like crazy. The ammonia is still 0 ppm, and the other fish hasn't been showing any of this behaviour.

Edit: I haven't noticed him rubbing himself since I added more salt. But I'm still going to keep an eye on him, I just don't believe it would be fixed this easily

 

[Sinuhe]

Another update: since I added more salt yesterday, I haven't noticed any rubbing. It seems either the salt is helping, or then it was only something temporary in the first place. Still keeping an eye on him, tho.

 

[Allivymar]

Excellent give us an update in a few days and let us know how things are going!

 

[Sinuhe]

An update: during the last week, I've seen both fish rub themselves on a 2 occasions. Most of the time they're still acting normal (and they even bred last week, as told in another topic). I didn't see any flashing for several days until today, after I added some plant fertilizer for the first time, and also added some crushed coral to the filter to harden the water a day or two ago (have yet to test the water for the hardness after that). Would you think that rubbing that sporadically, with otherwise normal behaviour and looks could still be a sign of parasites, or more just about changes in the water that irritate them (the tank is still cycling)?