copper sulphate vs. cupramine and testing

[waterlily]

I'm treating my fish in a 10 gallon hospital tank with Red Sea's copper sulphate. That tank water tests 0.25 ppm with Red Sea's test kit. I read that cupramine is safer than copper sulphate, so I bought Seachem's copper test kit and a bottle of cupramine. Seachem's own reference solution that is included with that kit is supposed to correspond with a value of 0.5 mg/L, but I'm only getting a faint blue color with it, corresponding to maybe 0.1 mg/L. I had my co-worker perform the test and she got the same result. My tank water is getting a similar reading with the Seachem kit. I made my own reference with 2 liters of deionized water and 0.1 ml of cupramine and the Seachem kit read it as 0.5 mg/L. Seachem says to use 1 ml of cupramine per 40 liters of tank water on two consecutive days to reach a concentration of 0.5 mg/L, so I just reduced the volumes equally calculate the proper amounts to add. I called Seachem and they're sending a new reference to me. The guy at Seachem also said that ppm = mg/L and that the Seachem kit will also read copper sulphate. Does this sound right to you? He suggested doing water changes to get my hospital down to a zero copper reading and then using Cupramine per Seachem's directions.

My questions for you are:
1) Is ppm the same as mg/l?
2) Does the Seachem kit read both Cupramine (a non-chelated form of copper) and copper sulphate the same? In other words, do they both measure only copper or would their other ingredients alter the reading somewhat?
3) Do you have any idea if mixing the two forms would be detrimental to the fish? (ie. Would it be okay if I didn't totally get rid of the copper sulphate before adding the cupramine, so long as I did not exceed 0.5 mg/l on the test kit?)

[Randy Holmes-Farley]

Does this sound right to you?

To the extent that I understand the kits involved 9which is not that great), yes, that makes sense.

Is ppm the same as mg/l?


Close enough, yes. It is off by a few percent, but the kit isn't that precise anyway.

Does the Seachem kit read both Cupramine (a non-chelated form of copper) and copper sulphate the same? In other words, do they both measure only copper or would their other ingredients alter the reading somewhat?

I'd have to rely on Seachem for that information. I know that soime kits will not read Cupramine well, but Seachem would be the experts on what their kit can read.


Do you have any idea if mixing the two forms would be detrimental to the fish? (ie. Would it be okay if I didn't totally get rid of the copper sulphate before adding the cupramine, so long as I did not exceed 0.5 mg/l on the test kit?)


I can't imagine that being a problem.