Please help! All of a sudden losing fish..

[roomtobelieve]

I have a 29 gallon tank set up that has been running about a month. I seeded it with decor from the old 10 gallon and ran the 10 gallon's filter alongside the 29 gallon's filter. Both were aquatech filters that were rated for the size of the tank they were in. I do 1/3 water changes weekly and treat the water with Prime and Nutrafin Cycle as well, since it is a fairly new tank. Water parameters were good at one week of running it (0 ammonia, 0 nitrite, ph of 7.6 and nitrates have hovered at 10 ppm) The water conditions have stayed consistent.

We have one live plant in the tank (pennywort) and other wise it is planted with plastics and a large plastic driftwood piece. The fish that were transferred into this bigger tank included:
5 neon tetras
1 spotted cory (1 inch)
2 male guppies
1 male swordtail (2 inches)

They lived happily and healthily until this past weekend. We acquired a small panda cory and added him to the tank as companionship for our spotted cory on thursday , then left town on Saturday. I put a feeding disk (gel based, tetra weekend) in the tank and since we returned Sunday night, I wasn't worried.

Well, Sunday I noticed we had lost 3 tetras and the feeding disk was untouched. I assumed they just hadn't eaten, read horrible reviews on that disk and thought I had found my answer. Everyone else seemed fine. Water was perfect (before mentioned conditions) On Tuesday night I noticed the swordtail had spent a lot of time near the top of the tank and upon looking closer, he has a bloody looking pop eye on the right side. I went today and bought API Melafix (for bacterial infections and pop eye) to treat the tank, and when I got home, performed a 1/3 water change, added Melafix and Nutrafin Cycle. It wasn't until I was vacuuming the tank and stirring the sand that I noticed my spotted cory was dead. He looks normal - no injury, just dead. What is going on?! The only new addition was the panda cory and he seems happy and healthy. I don't understand....

Can anyone shed light on this? I hate for my swordtail to suffer with his eye like that and I don't want to lose anymore fish....

 

[treemanone2003]

I can't help with any of the meds because (knock on wood) I've never had the need for any. Quite honestly, you went against what others had advised in your other thread about getting the new tank going. It's a mistake, sorry it happened, your forgiven. Let's move on.

First we need some more info to help. All the water parameters. Have you tested since this has happened ? There may have been a spike as the other filter is building up BB and the addition of the new fish. Also it's quite possible since you added the new one, and did not QT it for a period of time, it came home with something and it's now in your tank decimating your stock. Are you running both filters ?

If your going to use meds, dose according to instructions, or let somebody else suggest something possibly better, and most of all, make sure you remove the carbon. If not, the meds will not be effective.

 

[roomtobelieve]

I must have misunderstood what they told me on the other thread. I was told 'Put both filters in the 29 and go ahead and add the fish too. No need to wait. The 10 gal filter is already seeded from the tank. You'll build up more bacteria in the new filter, but I agree to keep both filters permanently.' I guess I'm just confused about which thing I did wrong.

I have tested the water since the pop eye occured yesterday. The water readings were 0 ammonia, 0 nitrite, ph 7.6 and nitrates 10ppm. That was late last night. I will be testing again tonight since I did a water change this afternoon. I didn't test the water after the tetras died on Sunday because everyone else in the tank seemed fine and I had assumed it was the food thing.

I had both filters running until about 3 hours ago when I changed the water. I took out the old 10 gallon filter because it needed to be changed anyway and I haven't put it back in yet. So, I am only running the Aquatech 20-40 gallon filter right now. What would you recommend? Run both or leave the 10 gallon out?

The Melafix says to dose 15 ml per day for 7 days in cases of sickness, so that's what I'm going to do. It's basically tea tree oil, so hopefully nothing too harsh in it. What do you mean when you say to remove the carbon?

 

[roomtobelieve]

Update: my swordtail just died.

Remaining fish all still look and act healthy.

2 tetras
1 panda cory
2 male guppies

should I continue the melafix treatments? I'm feeling lost here... I'm also worried about my schooling fish who no longer have schools. They're going to be stressed, but I'm afraid to add more fish until I know what's going on.

 

[Mebbid]

I would say skip the melafix. It is at best a band aid and not suited to treating a full infection. Another reason to stop use is that it is dangerous to cory cats since it can damage labyrinth organs.

My only thought is that it could have been an ammonia spike but even that is a bit of a long shot since your nitrates don't indicate increased ammonia.

What exactly was the feeder block that you used?

 

[treemanone2003]

I must have misunderstood what they told me on the other thread. I was told 'Put both filters in the 29 and go ahead and add the fish too. No need to wait. The 10 gal filter is already seeded from the tank. You'll build up more bacteria in the new filter, but I agree to keep both filters permanently.' I guess I'm just confused about which thing I did wrong.

I have tested the water since the pop eye occured yesterday. The water readings were 0 ammonia, 0 nitrite, ph 7.6 and nitrates 10ppm. That was late last night. I will be testing again tonight since I did a water change this afternoon. I didn't test the water after the tetras died on Sunday because everyone else in the tank seemed fine and I had assumed it was the food thing.

I had both filters running until about 3 hours ago when I changed the water. I took out the old 10 gallon filter because it needed to be changed anyway and I haven't put it back in yet. So, I am only running the Aquatech 20-40 gallon filter right now. What would you recommend? Run both or leave the 10 gallon out?

The Melafix says to dose 15 ml per day for 7 days in cases of sickness, so that's what I'm going to do. It's basically tea tree oil, so hopefully nothing too harsh in it. What do you mean when you say to remove the carbon?

You got most of it correct. The part you missed was I. The last post by jglover that said don't add any MORE fish. Just add the existing fish.

If you've already gotten rid of the filter pad from the 10, it may be too late. As well, if the pad doesn't remain wet, the BB will die off. Hopefully the other filter has established enough now.

As I said before about the meds, since I've never needed them, I can't comment on them. If your treating a tank with any meds, YOU MUST REMOVE THE CARBON. It will remove the meds before they have a chance to take any effect on the sickness in the tank.

 

[treemanone2003]

Update: my swordtail just died.

Remaining fish all still look and act healthy.

2 tetras
1 panda cory
2 male guppies

should I continue the melafix treatments? I'm feeling lost here... I'm also worried about my schooling fish who no longer have schools. They're going to be stressed, but I'm afraid to add more fish until I know what's going on.

Adding more fish is the worst thing you can do. DON'T ADD ANY FISH !!! You need to get this under control or your LFS is gonna love that you like to spend money. The fish will be fine. Please fill us in on the mystery gel food thing. It may help to figure things out.

 

[roomtobelieve]

True, I added a fish. Ugh, that's so frustrating. He was a gift to my son and I thought he was so tiny it couldn't hurt. Obviously I was wrong.

So, the feeder I used was the Tetra weekend gel feeder.
Thanks for all of your help. I'm absolutely not putting any fish in there until this is resolved. I'm not interested in spending money OR being a fish killer.

 

[roomtobelieve]

I do still have the filter from the ten gallon and it's damp. Should I put it back in?
The feeder was called Tetra weekend 5 day gel feeder. It was a two pack and I dropped in one disk. It was completely unchanged when I returned less than two days later.

 

[treemanone2003]

YES !!!!

Edit : FWIW, the fish can easily go 3-4 days without food.

 

[roomtobelieve]

Just updating. Everyone else is still fine and healthy. Water tests are good- 0 ammonia, 7.6 ph and nitrate at 5 ppm. I had a slight jump in nitrites- up to .25 ppm and then back down within 12 hours, which I wonder if the melafix could have caused. Otherwise we are in a good holding pattern. I'm still at a loss as to what happened except that maybe the panda Cory had something on him when he came into the tank. I feel really badly about that.

I am in no rush to add fish but am curious as to how long I should monitor and wait before I do so. My only concern is the tetras and Cory not having any kind of school. Should I wait a week? A month? How do I know when the tank is safe again?

 

[roomtobelieve]

Well, it's been a week and everything is stable. How do I know when the tank is ready to add a few fish? Nothing big - just a few tetras so the stragglers have a school. Don't want to jump the gun.... can anybody tell me what I should be looking for to know when the tank is safe?
Thanks.