Cardinal Tetras Keep Dying

[CleverBs]

My cardinal tetras keep dying one by one

I bought 5 like 5 days ago and they are all completely fine, so I went and bought 5 more however this time I got them from Petco instead of petsmart, and well they were a little sickly but i thought hay ill give them a good home. however they all died that night. so I took them back and got my money back then went to Petsmart to get more of the ones I have that are fine, however I lost 3 of the 5 I bought yesturday. Now I have read they are very sensitive fish so maybe I just got some that are senstive from petsmart (the ones from petco I knida knew would die but wanted to give them a better chance then they would of had at petco). My water is PH: ~7.9 Ammonia: 0 Nitrate: 0 Nitrite: 5.0 (may have nitrite and nitrate mixed up lol what ever one is messured on the larger sacle is 5.0 so its a good thing) I do have hard water and I know they like soft water so is this more then likely the problem? should i just get my money back for them and get them again once I have my RO/DI system?

 

[bruinsbro1997]

How long has your tank been established?
IF nitrites are actually 5.0 that's not a good thing at all.
Your pH seems a little high for cardinals but that shouldn't be the problem. THe problem is that you need to find out if they're getting them wild caught or not. Wild caught are a lot more sensitive. Another contributing factor is the conditions at Petco and Petsmart, wild-caught fish could easily become super-sensitive.

 

[FishN00b83]

I would ask where they got them from first, then start making decisions. If you do decide to use RO or RO/DI, make sure you put the trace elements and buffers back in the water before you put fish in the tank. Freshwater fish need a degree of gH and kH and will die without them.

 

[CleverBs]

My nitrate is 5.0

I'll be mixing tap water with my ro water. I'm not sure were they came from. And I'm 99% sure none of the employees at petsmart have a clue were they came from. My tank has been established with perfect water for about a week and a half.

 

[FishN00b83]

You said you have hard water, what is your gh and kh? They do like soft water, if it's really hard that could be your problem.

 

[CleverBs]

Not a clue i don't have a gh kh test kit. But its rather hard.

 

[librarygirl]

How did you acclimate them to the tank? If you introduced them too quickly the change from the tank water at the store and your water could have been an issue.

 

[CleverBs]

I float for 15mins then add some of my water for about 10-15 mins then put them in.

 

[bruinsbro1997]

I would try drip acclimation and see how they do.

 

[CleverBs]

I am even more alarmed now that my Cardinals are no longer dying but now I just had 2x Serpae Tetras die in the last 5 hours. They all look healthy and fine then one died out of no place, so i did a 25% water change, soon as I was done boomb another one gone. What could be the problem? I checked my water and its perfect Ammon: 0 Nitrite: 0 Nitrate: 5 water temp: 80F, NLS Thera +A Food 5 Days a week, 1 day no food, 1 day brine shrimp. Tank has Eco-Complete, Rocks, Quite a few plants (that i just put in last night). I cant figure out what could be the problem? the Serpae tetras I have had for 15 days and never had one die or get sick, why would 2 just die all the sudden?

 

[-Mac-]

Did you mix the pet store water with what's in your tank?

 

[CleverBs]

Did you mix the pet store water with what's in your tank?

No never, I always get them out with a net and put them in my tank.

 

[CleverBs]

woke up this morning 3 more cardinals dead....no idea whats going on...it almost seems like my Serpaes are killing them could this be the case?