There all dead!

[HAireman]

just yesterday i needed to add hardness to my tank. didnt have anything available so i used my brothers hardness for his turtle with added calcium and within half a hour most of my fish were dead only my kissing gouramis and pleco and long fin albino bristle nose survived. i killed 2 frontosas 4 d. comps (eye biters) three calvus and a breeding pair bristlenoses. and 50 bristlenose fry

can anyone tell me what exactly killed my fish?

and give me the drive to start again!

 

[tropicalmackdaddy]

What is "hardness for my brothers turtle tank"? And why did you need to add hardness?
Sorry for what happened, loosing all that fry really stinks

 

[leggey]

Do you mean to increase the ph ?

 

[insecurity]

Unless your water is overly soft (like less than 5dH), you shouldn't have to worry about hardness at all.
As well, most (there are exceptions, because there are more sensitive fish) thrive in water hardness parameters ranging from 5dH to 15dH, which is a wide range.
BUT- if your aqaurium water needs its hardness balanced, then the best water is to add small amounts of soft (rain) water or hard (well) water. Just remember to properly treat your water with water conditioner before adding it- you don't want to add those nasty chloromines to your water!

 

[tamtam]

just yesterday i needed to add hardness to my tank. didnt have anything available so i used my brothers hardness for his turtle with added calcium and within half a hour most of my fish were dead only my kissing gouramis and pleco and long fin albino bristle nose survived. i killed 2 frontosas 4 d. comps (eye biters) three calvus and a breeding pair bristlenoses. and 50 bristlenose fry

can anyone tell me what exactly killed my fish?

and give me the drive to start again!

So you added something to your water to up the PH?? What was it at and what were you aiming for? My guess is either the product you used is not good for fish or(and this is what I think) the change shocked your fish. A stable PH is more important than the number itself usually and I always advocate against any chemical products. If you really need to up your PH I would suggest some crushed coral in your filter instead. Keeps things far more stable then the ups and downs with other products.

 

[absolutangel04]

Sorry about your fish.
Since you added some sort of substance to the tank and then half an hour later most of your fish were dead, I think it is fair to say the substance you added killed them.
I don't know what you mean by, "adding hardness." If you can explain a bit more about the tank's history and parameters, we can help you figure out how better to handle a similar issue in the future. Many substances sold to alter water chemistry like pH can cause swings that are harmful to the fish. That is likely what happened here.

 

[bobc4d]

I work at a water treatment plant. our water is very soft, <25 mg/l CaCO3. what causes natural hard water is higher levels of calcium and magnesium. our soft water has not been a problem with my tanks