Sudden die off - HELP!

[OneFishBlueFish]

Greetings everyone! Today I came home from running errands and was greeted by tragedy. I have a 100 gallon freshwater tank and had a few native fish in the tank, bluegill and one bass. The bass and a few bluegill were added to tank (already cycled and established with one bluegill) approximately a week ago. The fish seemed okay, however were understandably stressed from being caught, however the bluegill quickly perked up and started eating.

Yesterday evening, my husband had noticed white spots on the bass and a bluegill. The white spots were on the gill-plate of the bass and tail fin of the bluegill. My husband believed this to be ICH, however I believe it may have been cotton-wool. My husband attempted to treat the tank with "jungle" ICH treatment according to directions. However, instead of removing only the carbon media, he removed all of the internals. I did not notice this until I returned home today and the water was extremely foggy and the fish were in obvious distress/trying to jump out of the tank.

The bass and three of the bluegill ended up dying, and the largest bluegill are stressed and gasping at the surface. I added and additional air stone, put the media back in the filter and added "AMGUARD" as ammonia levels went through the roof. Is the tank trying to recycle itself? Should I proceed with a fish in cycle to try and save the remaining fish? I want to keep this tank and bring it back to health but need advice before proceeding, as I am new to this.

 

[Aiken Drum]

If the media was out of water for more than 2 or 3 hours then the microbes responsible for your cycle will have died off. If it was kept wet, but not oxygenated, for instance in a bucket of water it will live a few days. If its kept wet and oxygenated, for instance in a bucket of water with an airstone, 2 or 3 weeks.

Easy way to tell if your tank has lost its cycle. Do a big water change, test 24 hours later, if you see ammonia or nitrite you have crashed your cycle and will need to recycle the tank.

Question about your ich treatment. Did you up the water temperature? Ich has a lifecycle that is temperature dependant, and the medication needs to be in the water for a complete life cycle. At typical tropical aquarium temperature, the lifecycle is 3 or 4 weeks. At 82f/28c the lifecycle is about a week. If you don't elevate the temperature you need to have the medication in the tank for much longer or you risk not killing all the parasites. Raise the temperature of the water to 86f/ 30c for a week and the temperature alone can usually kill the parasites without the need for medication.

If you have some photos of the infection we can look at diagnosing the issue for you.

 

[OneFishBlueFish]

Thank you!

The medium was left in just a regular bucket and unfortunately, it was rinsed with chlorinated water, so I am sure the helpful bacteria has all been killed off.

I will try to get some pictures of the affected fish, I am sure it was not ICH however (as the white "spots" were fuzzy and moldy? looking. Almost all inhabitants of the tank have died except for three. I checked the bass's body over and he has dark black patching on his stomach, so definitely ammonia burns there. Doing a water change tonight and retesting. Will post results when I do.

I think I may follow the "new tank syndrome" protocol that was posted to this forum. Is this a good idea?

 

[Aiken Drum]

I think I may follow the "new tank syndrome" protocol that was posted to this forum. Is this a good idea?

Not exactly sure what post or thread that protocol is from, perhaps provide a link to the thread you read.

Cut back on feeding, test daily, if ammonia + nitrite combined is above 0.5ppm then water changes until the parameters are below that combined target. When you are comfortable that water parameters arent elevating too fast then return to full feedings. When your daily water testing consistently shows zero ammonia and nitrite you are cycled for your current fish and can add a little more bioload. Expect parameters to elevate again with higher bioload, so rinse and repeat with the testing and water changes until you are again seeing consistent zero ammonia and nitrite before adding a little more bioload.

 

[Colin_T]

Do a huge (80-90%) water change and gravel clean the substrate to dilute any ammonia in the water. Get the filter media (not the carbon tho) back into the filter. Increase aeration to maximise the oxygen in the water.

Post pictures of the fish so we can confirm white spot