New Tank, New Hobby; Sick Cory

I have had a tank with fish in it for three months. There were orginally 6 zebra danios. There are also seven cories (albino, bronze belly and false julii), 10 cherry shrimp and our latest edtions three weeks ago were two dwarf gouramis: one red flame and one blue neon. In the last four weeks I have changed half my aqaurium gravel for aquarium sand, added a madagascar lace bulb and the two gouramis. Over the last week one danio died and one has been poorly by not eating and only swimming at the top of the tank away from its group. Yesterday I noticed one of the false juliI cories had the dorsal fin looking a bit 'shredded' and wasn't swimming so happily around the tank. This morning it is going from floating vertically to swimming down to the bottom with it looking a real struggle. The tank has no ammonia or nitrite but nitrates are 10-20ppm. I have a 80l tank and change 10-20l a week and test the water weekly.

Now I have moved the fish into a shallow tub (with holes) in the tank as I do not have a hospital tank and I feel the gouramis are bullying it. The cory seems to have red gills/side. There is no ammonia in the tank. It seems to be floating vertically or on it's side and breathing frantically. If anyone has any advice it would be really appreciated.

Edited to add both fish the cory and danio have died in the past hour.

 

Re-home the gourami's or get a tank FOR JUST THEM A.S.A.P. sounds like a bad case of moving around the tank decor and changing it which can stress them out and bulling from the gourami's. Is the tank a 20G (80L) long or high? nitrates are good but I would do a water change to lower them a tad bit.

 

Welcome to FishLore!

Actually, I think you are going to have problems with your Dwarf Gourami's. As they mature, they will start fighting one another, until one kills the other. They really do not get along with one another. Sometimes, in a large enough tank, with lot's of stuff to break up their site-lines you can get away with having more than one, but 80l is sadly not large enough. I learned this lesson the hard way by having two in my 46g.

 

Hello. The 80l tank is high. It has bogwood with moss and a large stone creating an arch. The tank is also filled with lots of plants so I was hoping there would be enough cover and space for all of our tank buddies. We planned on getting one dwarf gourami but the aquairum shop recommended getting two as they would be happier as a pair. The research I did led me to only getting one gourami but I went on the shop's advice. The shop is pretty reputable and not a chain petshop so I thought I could trust their advice. Do you think they would accept them back? I am not in a position where I could buy another tank right now.

They had been chasing each others' tails now and then but nothing alarming or consistent but I have watched them pick on the sick fish today until I moved them into a little holding tub. And watching them now one of them has chased another catfish.

I looked over the fish when they were dead and the danio had a red spot on his belly and the cory had one very red gill and on the other side some red along the side of its body. I feel like I have a death tank, I am feeling really awful.

Do you feel I should do a big water change to reduce the nitrates? 50%? I had read to try and do a big water change but do 10% daily for a few days so as not to shock the fish.

 

Hello. The 80l tank is high. It has bogwood with moss and a large stone creating an arch. The tank is also filled with lots of plants so I was hoping there would be enough cover and space for all of our tank buddies. We planned on getting one dwarf gourami but the aquairum shop recommended getting two as they would be happier as a pair. The research I did led me to only getting one gourami but I went on the shop's advice. The shop is pretty reputable and not a chain petshop so I thought I could trust their advice. Do you think they would accept them back? I am not in a position where I could buy another tank right now.

They had been chasing each others' tails now and then but nothing alarming or consistent but I have watched them pick on the sick fish today until I moved them into a little holding tub. And watching them now one of them has chased another catfish.

I looked over the fish when they were dead and the danio had a red spot on his belly and the cory had one very red gill and on the other side some red along the side of its body. I feel like I have a death tank, I am feeling really awful.

Do you feel I should do a big water change to reduce the nitrates? 50%? I had read to try and do a big water change but do 10% daily for a few days so as not to shock the fish.

The store will take the gourami back (should) if not someone on here is bound to take it. As long as the Parameters of your tank and tap water aren't to different do a %50 water change at once. The red spot was probably the gourami hitting them and the red gills was probably from stress.

 

I am going to phone the store tomorrow and see if they will take them back, thank you.

I just checked my tap water and interestingly the nitrates are 10-20ppm. I wonder if that is due to the drought weather we have been having in the UK. The biggest difference is ph which is about 7.6 which is lower than the tank at 8.2. Would it be safe to do such a large water change with that difference in ph? Two stores advised me not to worry about ph so much as we live in a hard water area and the tanks that stock come from are in hard water too.

 

Hello! It was a sad week for our tank losing our first fish. I just thought I'd update. The shop were fine with me returning the gouramis, though a little surprised when I said they had been aggressive.

I did a 50% water change and have been feeding every other day.

The difference in the fish in our tank is massive. The danios are once again zooming around the entire tank instead of staying huddled at the top. The cories are happily mooching at the bottom (which they always were) but are also happy to mooch on the bogwood and spend more time swimming up the tank sides. The cherry shrimps have come out of hiding and yesterday for the first time ever I saw the first lot of baby shrimps! It is like the whole tank has relaxed and peace has been restored.

In hindsight it was obvious it was the gouramis that upset the balance but being green to the hobby I felt it must be illness and not stress.

So I just wanted to say thanks so much for your input, it has been a real learning experience for us all. We are going to wait a good few weeks and decide on what fish we would like to school in the tank and start building up the numbers slowly.

 

Hello! It was a sad week for our tank losing our first fish. I just thought I'd update. The shop were fine with me returning the gouramis, though a little surprised when I said they had been aggressive.

I did a 50% water change and have been feeding every other day.

The difference in the fish in our tank is massive. The danios are once again zooming around the entire tank instead of staying huddled at the top. The cories are happily mooching at the bottom (which they always were) but are also happy to mooch on the bogwood and spend more time swimming up the tank sides. The cherry shrimps have come out of hiding and yesterday for the first time ever I saw the first lot of baby shrimps! It is like the whole tank has relaxed and peace has been restored.

In hindsight it was obvious it was the gouramis that upset the balance but being green to the hobby I felt it must be illness and not stress.

So I just wanted to say thanks so much for your input, it has been a real learning experience for us all. We are going to wait a good few weeks and decide on what fish we would like to school in the tank and start building up the numbers slowly.

So glad to hear everything is well! You could do some harlequin rasboras they are my favorite schooling fish and are SUPER peaceful!

 

They have been top of my list since day one! I really wanted rummy nosed tetra but the tank is taller than it is wide. It will look lovely with lots of harlequins! Thanks for the heads up.