Tropical Fish Keeping - Aquarium fish care and resources

Tropical Fish Keeping - Aquarium fish care and resources (
-   Tropical Fish Diseases (
-   -   Tetras keep dying... Why? (

pog0 09-21-2009 12:35 AM

Tetras keep dying... Why?
Hi Everyone,

Long time lurker, first time poster. I want to thank everyone for the vast amount of info I read before getting into my fish problems. THANKS!

Anyway, I have a 29 gallon tank stocked with 3 Yo-Yo Loaches, 1 common Pleco, 2 Powder Blue Rams, and now 7 Neon Tetras (used to have 10). Before the Rams were added, everyone seemed to be fine... I had 2-3 smaller Tetras than the rest of the group but they got their food whenever it was feeding time. They were together for about 2 weeks. After about 2 weeks, I added some driftwood that I soaked for a week and constantly changed the water that was in the bucket for the wood. In about 2-3 weeks, I have lost 3 Tetras. The only thing that changed was the wood, but never heard of wood causing fish to die. I do know it softens the water a bit, but that much to kill fish?

I change my water every week - 8 or 9 gallons. I use Prime for water prep. None of the Tetras or other fish have any other diseases. I looked up Neon Tetra Disease and one of my smaller Tetras has a bent spine but all color is there. All the bigger Tetras look fine. I did a basic water test and everything passed with flying colors, just no test for water softness. I don't want anymore of my Tetras to die... Any help is appreciated.


Byron 09-21-2009 11:02 AM

It is unlikely the wood is causing the tetras to die; if there was something toxic in the wood the other fish would show symptoms. Wood does lower hardness and pH but only very minimally. This is not a problem.

Your weekly partial water change is excellent, and Prime is a good water conditioner.

When was this tank first setup? What is your tank water pH? And temperature?


pog0 09-21-2009 12:47 PM

Tank has been established for quite a while - ~1 year.

Temp is left at 80F. Not sure what pH is off top of my head. I will check it again tonight when I get home.

Byron 09-21-2009 01:38 PM


Originally Posted by pog0 (Post 246298)
Tank has been established for quite a while - ~1 year.

Temp is left at 80F. Not sure what pH is off top of my head. I will check it again tonight when I get home.

One thing does present itself; the temp is high for neons. I realize 80F is good for the blue rams, in fact the lowest it should be for this fish; and the loaches (Botia almorhae I assume is the species) are fine at 80F snce they are native to calm water pool areas of highland streams in India & Pakistan. But neon tetras prefer slightly cooler water, around 77F. Three degrees might not seem like much, but to the fish's metabolism it can be. However, I am not suggesting the temp is the problem here, just something to bear in mind. I'll wait for the pH info.


pog0 09-22-2009 12:28 AM

pH level is somewhere between 8.0 - 8.2. San Diego water, well Southern California water is always around there.

Not sure if pH would cause it though since it has always been around there since day 1. Temp right now is between 78 and 80F. My heater is set to 80F, but I will drop it down to 78F... But I also wouldn't think that would cause it since it has always been around 78-80F since I put fish in there.

Byron 09-22-2009 03:05 PM

The pH at 8.0 is very high for the rams, and the neons too. However, neons are mainly tank-raised fish now and generally seem to be better able to cope with higher pH and hardness [I'm assuming the water is on the hard side to match the high pH]. If the neons came from a store with similar water, and that doesn't do anything to adjust their water to a lower pH, it should be OK. I am not so sure about the rams at that pH though.

You had the neons for 2 weeks before they started dying, correct? And three have died in the last 2-3 weeks. I can only guess. Could be a reaction to the high pH/hardness, sometimes fish "cope" for a while but then they wear out and succumb. Or they may have had something genetic/parasitic from before; this does happen. I had a group of 11 false neons for 4+ months; then within one week 7 of them died. I'm at a loss for the reason, as the remaning four and everything else are fine.

A technical note on pH and hardness. Fish have evolved over millions of years to live in their environment, and while there have undoubtedly been changes to the envirnments the fish have continued to evolve accordingly. For thousands of years now--I'm thinking of rams, neons and similar South American fish--the fish have lived in very soft and acidic water. Their internal metabolism is geared for that water. Fish for instance "drink" by absorbing water into their cells through osmosis. Their internal blood pH has to equal that of their surroundings, so when the pH of the water changes, their system has to work to alter the pH of their blood, and this takes considerable energy; adding salt to an aquarium has a similar effect. A significant sudden change in the pH of the water can be catastrophic; adjusted slowly over long periods of time less so. This is why pH fluctuations in an aquarium are so detrimental to the fish. Some fish have a natural ability to adapt quicker to greater differences in water parameters; others do not, and some seem incapable. I can't say that this is the source of the problem with your neons, but it is one possibility.


aunt kymmie 09-22-2009 03:21 PM

San Diego tap water is as hard as it gets. When I tested mine I redid the test twice to be sure that the results were correct. As Byron states it's highly likely that the PH and the hardness are just too much for your neons.

gondo 09-22-2009 04:29 PM

I can help with the tetras but not the other fish as I am unfamiliar with them. First off since you're using prime (the best conditioner on the market) I assume you are using tap water. Therefore you have little control over your PH and hardness. Tetras like a PH around the 6.5 mark (slightly acidic). They also like soft water...say a total dissolved solids in the 50-100PPM range. These are just approximate but using tap water it's hard to even get close.

Using tap water has its advantages. It's very stable. Your fish will live, but they won't be happy, and flourish and swim around so vividly as they should without the proper water. What I do is use Reverse Osmosis Deionized water, add Kent Marine RO Right to reconstitute it to soft water, then add Aquarium Pharmaceuticals Proper PH 6.5. After testing my water is in the 6.5 range every time. This is what I use for water changes. I have very active and healthy fish, and also no algae at all.

I notice you do a 10gallon water change which is 33%. How often? I do a 4 gallon water change which is just over 10%. I try to do this weekly. Your 33% seems much.

Also your temp seems high for Neons. Around 75'F is better. I used to use tap water and 80'F water for Neons in a 29 gallon and they lived because of stable PH of the ultra buffered city water. But the Neons where always bunched together at the bottom of the tank in the same corner. After switching to 75'F and using the soft, acidic RO water I have tetras that actually school and swim all over. It made a big difference.

I also have Corry catfish and Horseface Loaches in the same tank and all prefer the same soft acidic water. Get fish that are compatible water wise, and if you don't want to make your own water get fish that like the water coming out of your tap.

pog0 09-23-2009 04:28 PM

Thanks for the replies guys.

My tank has been established for over a year with the following fish - Pleco, 10 Neons, 3 Yo-Yo Loaches. No change in temp which is between 78-80F. I use tap water and Prime for water changes. When I FIRST got the Neons, 3-5 died since the tank wasn't fully established. After tank sat for a month or so, I put however many Neons to make 10. They all lived and actively school together and swim alone.

The tank seemed a bit boring, so I purchased 2 Powder Blue Rams. Everything was cool. Got bored with the decorations and removed my fake log and bought 3 pieces of driftwood. Soaked wood for a week, changing water everyday. Put the wood in with next water change (every week unless I get lazy). I got lazy one week and went to two weeks for my water change and noticed I was missing a Neon. Body completely disappeared - presumed eaten as soon as he died. Did another water change before 1 week vacation - down to 8. Water change after vacation - down to 7.

If the pH was an issue, wouldn't the Neons go a while ago instead of now? Could it be that since Neons are sooooo sensitive that the driftwood is shocking their system?

gondo 09-23-2009 04:34 PM

A stable PH is more important than a wrong PH. A proper PH that swings will kill no matter how good the PH is. A totally wrong PH that is stable will be better. You fish will live, but will not be happy, not live as long, and are more susceptible to disease. You use tap water so you have very stable PH.

If no bodies are to be found then I suspect they are being eaten.

All times are GMT -5. The time now is 06:20 PM.

Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

For the best viewing experience please update your browser to Google Chrome