White Clouds being picked off one by one...

weekend cook

My tank has been cycled for three weeks now. I used TSS, 6 white clouds and 5 zebra danios. Readings have been steady at 0 ammonia, 0 nitrites and 5 nitrates. I added some cories two weeks ago. Everything was going fine. I lost one White Cloud last Wednesday. I wrote it off to a temp spike I had. Temp went to 82 degrees and I thought it may have stressed one since they like cooler water. Got the temp back down to 75 and did a 30% water change. Readings held steady at 0,0,5. I added two swordtails last Saturday. I then lost the second white cloud on Sunday night leaving me with 4. All 4 seemed fine when I left for work this morning (Tuesday) and when I got home, I only had three. I found another White Cloud floating on the bottom. I lost three fish in six days. It only seems to be affecting the White Clouds. The remaining stock in the tank is active, eating and seems OK.

I took the remaining three and placed them in a 2 gallon quarantine tank. I had to do an emergency LFS run for a pump and filter. I took some gravel from my sons cycled tank and some media from my tank. I also threw some prime in for good measure. Hopefully that tank will be cycled shortly.

A couple of observations. 1) I noticed the danios were bullying and chasing the white clouds around. Not all the time, but the chasing was fierce and all over the tank. 2) This is a change in behavior as the two schools usually combined and swam nicely around the tank. 3) In two months, I bought 11 fish from this LFS. Now 5 of the 11 have died. I bought 15 fish from 2 other stores and haven't had a loss yet.

Here are my thoughts.
1) I will do another water change in the 55 gallon tomorrow in case there is something in the water.

2) I don't think the swordtails brought anything into the tank as I lost my first white cloud before I introduced them.

3) If I don't lose the remaining three in the quarantine tank, the deaths could have been caused by stress from the danios bullying.

4) If I lose the 3 in the quarantine tank, I have no idea what killed them unless my 55 gallon stock starts dying.

5) This LFS appears to have poor quality stock and may be the reason for this round of deaths.

Any thoughts would be appreciated.


Hey Weekend Cook, welcome to fishlore!

I used to be a big fan of the whiteclouds too, I have one left. What I had observed is a change in the shape of their belly - changes to be squarer (not sure the proper way to describe it), an they had become pale. Dropped off one by one.

I have my suspicions that white clouds may be susceptible to a disease other alike fish may not be.

Hope you have a better out come than I did. All I can advise is water changes....

ALSO: What is the GH & KH hardness of your water?

weekend cook

Not sure if I am reading the API test correctly but the KH is 6 and the GH is 9.

The three clouds in the quarantine tank made it through the night. Now one of my cories is acting weird and rubbing up against the air hose and plant leaves.

UPDATE: Gotta go to work, but now he is schooling with the others and rummaging around the bottom.
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Probably the results of being used to cycle a tank; just because the fish didn't die during the cycling doesn't mean it didn't kill them.

IMO and generally speaking of course, if fish keepers have studied enough to know that danios and white clouds are used to cycle a tank, then they have been exposed to enough knowledge and information to know that cycling a tank without fish is the way to go.

Good luck and I hope the others make it.


I don't have anything useful to add other than the adage about misery and company. I also had a problem with danios, but no other species in the tank.

In my very limited experience, I think some danios are just nasty little fish. I started with a school of eight. One by one, I found dead fish until they were down to three. There were at least two who were extremely aggressive, there was obvious fin damage on the casualties. I knew they prefer a school and thought maybe the aggression was because there weren't enough. The fish store agreed and said any less than five would probably swim each other to death so I got three more, bringing me back up to six. No five, one was dead when I got home.

Again, one by one they were picked off until there were only two left. I gave up at that point and figured I could either euthanize them both as a school was obviously not going to happen, or let nature take over. I'm sure it won't be popular, but I left the two of them in the tank. They've lived happily ever after.

So, were those two the problem all along? I honestly think at least one of them had been, he's was slightly bigger than the others so distinctive.

If I had it to do over again, I don't know what I'd do. I'm not sure I could euthanize an otherwise healthy fish, no matter what a psycho killer s/he may be.

weekend cook

I would have taken those two danios back to the LFS. If the danios that are in my tank start going after the other fish now, they will be going to the LFS. My LFS gives me exchange credit. Even if I didnt get credit, I would take them back as I wouldnt feel right euthanizing a healthy fish.


As for the GH & KH test. That sounds really low. I have a hagen set which is number of drops x 20. Maybe yours works the same? Hardness range is usually measures in the 100s.

If your fish are rubbing against things, that's a sign of velvet. This is contagious. You may want to increase your tank temperature and get some medication for this.

weekend cook

Update: I didnt lose any white clouds in the QT and they were looking quite active and needed more room (its only 2.5 gallons). My wife was also complaining about the bubbling noise from the QT as it sat on the kitchen counter. I bought two more white clouds and placed all 5 in the 55 gallon. I observed them and I noticed one Danio was very territorial and chased both white clouds and danios if they swam to the left side of the tank. All the danios and white clouds stayed on the right side of the tank. One white cloud got trapped over in the left corner and the bully was brutal to this poor fish. I though the white cloud was going to jump out of the tank.

Enough is enough.

In my sons tank, there is one Danio that is definitely subordinate to the other two danios so... I swapped the bully from the 55 gallon with the more passive danio from my sons 10 gallon.

Guess what, now all 5 danios and 5 white clouds school over to the left side of the tank. It looks really cool to see two species of fish school together all over the tank. The bully is holding his own to the other two fish in the 10 gallon.

I am pretty sure the 3 white clouds died due to the stress of bullying. I wish I saw it sooner. Sorry guys.

The cories are doing fine and stopped the rubbing behavior. I was worried that they caught something but they have been acting normal.
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