Gourami With Sores

Thank you for your reply
He is eating and swimming fine.
I have no other tank to put him in to recover

Three possibilities spring to mind - iridovirus, burning, lymphocystis.

Could he have burned himself on the heater? The sudden appearance does suggest a burn.

Was there any sign of anything before the sore appeared? Anything like a tiny pimple or raised scale?
Iridovirus is a distinct possibility as a lot dwarf gouramis bred in the far east are already affected by the time they arrive at the shop. But other symptoms of this disease include listlessness and colour change - he doesn't appear to have turned greyish and he looks quite perky in the photo. I would also expect a sore like that to develop from a small spot not just appear at that size.

Lymphocystis is the other thing that came to mind because I once had a betta with this disease. But in his case, it started with a raised scale which grew into a lump and took a couple of weeks to develop to the stage that looked like your gourami.


If it is a burn, he just needs lots of clean water. If it is iridovirus or lymphocysts (also viral) they are incurable. The female gourami is at risk if it is iridivirus and all the fish in the tank are at risk if it is lymphocystis.



If this was my fish I would set up a hospital tank for the gourami. Even a plastic storage box would work. He needs a filter and heater - steal some media from the current tank. Lots of live plants, even just a bunch of elodea, will help keep his water conditions good. Then change 50% of the water daily and watch him. And use separate cleaning equipment from the main tank, just in case of infection.
If it is one of the viruses, this will stop it passing to the other fish. Lymphocystis only passes on spores when the lump bursts open so if it does turn out to be this the other fish won't be infected yet. If it is a burn, it will give it chance to heal without the risk of the other fish picking at the sore.
With a burn, there is a chance that it could become infected. If you do set up a hospital tank it could be worth also treating with eSHa 2000 as a preventative. But don't use this in the main tank as all medication affects fish and you don't need to treat the other healthy fish.

All you need with a hospital tank is a container big enough for the fish to be comfortable. For a dwarf gourami around 25 litres would be fine. It doesn't need to be a tank, a brand new plastic storage box will be just as good. But it must have a cover, either a lid or an old towel draped over the top.
It will need a heater and filter, but you can steal media from the main tank for that. It does not need a light - in fact it is better without a light as without a light a fish will be less stressed and light can affect some medication should one prove necessary. You don't need a substrate for a fish like a gourami. Decor is important to make it feel more secure - if you can manage to get to a shop in the current weather a clump of elodia (aka erigeria) would be perfect as it is cheap so it doesn't matter that if there is no light and the plant eventually dies.

It does sound unlikely to be a burn in a Rio 125 (I used to have one). Could he have scraped himself squeezing through some decor? The size of the sore and its sudden appearance makes me think it isn't a disease. But if it is a scrape or burn it could get infected, something you need to watch for.

I'm sorry to hear that 


Another thought has occurred to me. If he was already sick, the other fish could have been picking on him. This is normal. Weak fish are easier to catch so they attract predators. It is a survival trait that fish will kill a weak member of their shoal so they don't attract predators. I know that gouramis are not shoaling fish, but the guppies and swordtails might have reacted to him as though he was one of them.

Following the loss of my male Gourami last week I see that my male Swordtail has a similar sore on the under side of his body.  Again on Sunday he was fine nad within 48 hours he is clearly very poorly.  He can swim but needs a lot of effort, if he stops he sinks.
Any ideas as to what is happening here.
All water parameters are fine when tested with Tetra 6-in-1 dip strips

Many thanks for your reply

The tank has guppies, sword tails, on female gourami, Cardinal tetras golden loaches and zebra danios. There are also zebra snails. Everything has been happy for over 12 months.

I introduced some more guppies in January and the male gourami in February.
When I saw the sword tail last night was the first time I noticed the sores. The gourami was ‘bumping’ him but I was not sure if this agression or because he was submissive.

If it is lymphocystis is there preventative action I could take and are some breeds more resistant.  I would hate to see the whole tank waste away

I have three loaches in a 125 litre tank. I bought all at the same time probably 14 months ago. There has not been a problem up to now.

Is this because they have matured or taken to bully boy (girl) tactics for another reason.

Can we now rule out a virus?

Thank you all for the valuable advice. I had no idea the loaches would do that.

I have been to my local store, they have given the same advice and agreed to rehome them and made some valuable suggestions as to other community friendly inhabitants

The Sword-tail is still with us but a bit bruised.