Neon school dying....

[DrNic]

I finally got a stable school of neons (~15) in one of my 29G tanks. I've had them in there for about 4 months I think and they were doing great. I was planning on adding some cardnials and a couple of dwarf gourami after new years.

Well this afternoon I did a standard water change (40%) on all my tanks. Suddenly all but 4 of the neons start swimming funny and are dying as I write this. The water chemistry shows no ammonia, no nitrate/nitrite, and a pH of 7.2 all standard for the tank. The thermostrip I have on my python also ensured that the water going into the tank was the same temp as what was already in there. All of my other tanks that had water changed at the same time seem fine.

Any ideas on how I managed to wipe out my neons at once?

[fish "r cool]

sorry about your loss.
maybe they were infected with a disease before you put them in the tank.:scry:

[Dave66]

Has to be a chemistry shock, Nic. It's fairly obvious, since they showed distress and died right after water change. IMHO 40 percent is far too large a change for something as sensitive as Tetras are to sudden large changes in water character, particularly pH, hardness and temp. Try doing 20 percent changes weekly. It's what I do, and I have a ton of Tetras, and haven't lost any in years.

Dave

[doug z]

Dave would know, Nic..

Unless you forgot to add dechlorinator or something, I would think that's your culprit..

Also, if it's been quite a while since your last WC (a month or longer), that will shock them, too..

That sucks.. :(

[DrNic]

Well I'm not sure what the reason for the mass death was. Everything seemed fine. Maybe the water change was just too much shock. At the moment there are 2 neons left and the rainbow shark, who wasn't visibly effected at all.

Given the massive problems I've had trying to get this neon tank together (this was the 3rd or 4th try) I'm thinking that I might just take the tank in another direction.... I'm just not sure what direction that is at the moment. :ssuprised:

[Davered00ss]

40% is a lot to change at once. I would check the hardness of the water. Also, I though neon's liked soft water and a pH closer to 6.8?

[Lady Hobbs]

I do large water changes in all my tanks but not in my neon tank. I think it's too much of a change for them and they are sensitive fish. Listen to Dave.

PS.....I've also had better luck with neons now that I keep the tank cooler. I was keeping mine near 80 and for me, neons do better at 74-76.

[Glub]

Just a side question since this thread's dealing with water changes.

But would a 10% change twice a week work as well? If neons are sensitive, would it perhaps be better to change the water twice a week in smaller amounts? Or would this be too much frequent disruption?

[Adrian]

This is one of the reasons why I don't buy neons. They seem to have a multitude of problems that can and most often do go wrong with them. I will stick with cardnals, as they seem heartier, and don't go thru a lot of stress when I do water changes. I have done 50% water changes, and they do fine with it.

Seeing as I just got an R/O system set up, I will have to really watch them now, seeing as they are use to the tap water I use. I think I will continue to use the tap water and add chloramx to the water. If it aint broke, don't fix it.....

[Lady Hobbs]

This is one of the reasons why I don't buy neons. They seem to have a multitude of problems that can and most often do go wrong with them. I will stick with cardnals, as they seem heartier, and don't go thru a lot of stress when I do water changes. I have done 50% water changes, and they do fine with it.

Seeing as I just got an R/O system set up, I will have to really watch them now, seeing as they are use to the tap water I use. I think I will continue to use the tap water and add chloramx to the water. If it aint broke, don't fix it.....

I believe with RO water you should use half tap and half RO because RO water is lacking in electrolytes. If using all RO, you need to add RO suppliment. Others that have and use RO can tell you better, tho.

[tort518]

How odd. I just had a number of my black neon's die over a 3 day period. Lost half the school. I checked my parameters and things were fine and my water changes are typically about 10 to 20 percent once or twice a week. PH is stable at 7.2, plenty of plants. Very strange to see it happen to someone else about the same rough time period.

The only change I made to the tank was moving the loaches and flying foxes out and putting the pygmy cories in. I've watched the parameters closely, nothing changed and I regularly treat to prevent ich and other diseases.

Things seem to have settled down now and no other fish were lost.

Good luck with your tetras, hopefully all has stabilized.

Jim

[Lady Hobbs]

How odd. I just had a number of my black neon's die over a 3 day period. Lost half the school. I checked my parameters and things were fine and my water changes are typically about 10 to 20 percent once or twice a week. PH is stable at 7.2, plenty of plants. Very strange to see it happen to someone else about the same rough time period.

The only change I made to the tank was moving the loaches and flying foxes out and putting the pygmy cories in. I've watched the parameters closely, nothing changed and I regularly treat to prevent ich and other diseases.

Things seem to have settled down now and no other fish were lost.

Good luck with your tetras, hopefully all has stabilized.

Jim

I highlighted the part that I have a question with. You regularly treat with what? No medications should be used unless you know for sure they have a problem like ick or disease. Especially if you are treating with something and only doing small water changes.

Could you explain further what you are treating them with and why?

[Northernguy]

I highlighted the part that I have a question with. You regularly treat with what? No medications should be used unless you know for sure they have a problem like ick or disease. Especially if you are treating with something and only doing small water changes.

Could you explain further what you are treating them with and why?

Something is wrong here for sure.
Do you take antibiotics when you do not need them?
They are never neccesary unless your fish are sick.
The best prevention of disease is a good water change schedule.