The Trigger

So I awoke from my slumber this morning to find my fish gasping for air at the surface. I tested the water immediately to find the nitrite reading off the charts! The only thing I did was treat the tank the night before with melafix as I've been doing for the past couple of days for fungus on my German blue rams tail. I used the recomende dosage and haven't had any problems since i started...until now. But this stuf claims to not hurt the biological filter!? Apparently it does. So what do i do? Obviously stop treatment and i cant do anything till i get home from work today. Anybody else have bad exporiences with this stuff?

gr33nthumb

Actually it does not harm the bio-filter, have never personally had an issue, or heard of anyone having an issue with it. Was anything changed? Substrate, filter media, big bio load change, large plant mass change? I would look at that type of thing. If it was an established tank then there had to be a large upset for the bio-filter to get screwed up! Throw some prime in there and wait it out!

The Trigger

Nope. The melafix was the only thing done to the tank yesterday. I'm perplexed. I've been treating for 5 days and the fungus has gone away. I haven't noticed anything wrong until this morning. It's very very strange. I put in a crapload of prime as i was running out the door. Im gonna do a water change when i get home and see if any damage has been done.

Zapins

Usually gasping indicates a lack of oxygen. The nitrate readings might be because something is decaying in your tank and has used up most of the oxygen in the process of decay. A water change is a good idea, but have a look around for areas of the substrate that might not have been cleaned in a while. Or for that matter anything large (snails/food/fish/shrimp/etc) that might have died.

The Trigger

Well I always keep good surface agitation all the time to ensure enough oxygen is getting to the fish. its only a 29 gallon but I do have a heavy plantload in there. What I didn't think about is that there could be a decaying corpse hiding behind the plants. I'll have to do a thorough check of the tank. Thanks for all the help. I'll update when track down a cause

The Trigger

Got home and tested the water and had a NITRITE reading of .25ppm. All fish are accounted for and not signs of decaying plants or food. Did a 75% water change and flushed out my eheim 2215. Still stumped on why the spike occurred in the first place. I wish I had some idea of what happened so i could avoid a scare like this in the future. Crisis averted for now

gr33nthumb

wow that is strange indeed. Zapins Idea was perfect, but if you dont have anything large decaying that is certainly a mystery! good to hear no one was lost. keep us updated!

The Trigger

Very strange indeed. thank you both for your help. I really appreciate it guys.

The Trigger

Update : tested water this morning and still reading small amounts of nitrite. Still no losses but I don't know if any damage has been done. Been bombarding the tank with prime and doing water changes. Hope this ends in the next day or two. Still no cause found.

jgmbosnia1

I had the same exact thing happen in my 90g. I woke up one morning to find two dead fish and the rest were gasping at the waterline. I put the bubblers on full blast and everything was fine after an hour or two. I did some searches online to find that we aren't the only ones. Supposedly the Melaluca oil in the Melafix creates a fine oil layer on the surface not allowing for oxygen exchange at the surface. BTW this happened on my third day of treatment. I never checked for nitrates. Hmmm.