I’ve done a little research on the web and have at least a partial answer to my question. The toxicity of chloramine differs for different organisms, but very low concentrations can be quite deadly. For example, a concentration of 0.8 ppm of Cl will kill half of juvenile killifish in two or three days. (This and the quotes below are from http://www.reefkeeping.com/issues/2003- ... /index.php .) A lower concentration for a longer time can have equally bad results. The recommendation in this article is to keep the levels below 0.005 ppm of Cl.
What does this mean for topping off aquariums? The article states: “This target of 0.005 ppm-Cl or less does not necessarily imply that all water used for aquaria must be that low. For example, an aquarium that tops off 2% of the tank volume daily (to replace evaporated water) will not have a chloramine concentration equal to the top off water. It will, however, have fresh chloramine added every day. Even if the chloramine added each day is broken down in the aquarium before the next addition (something that is likely, but not demonstrated for aquaria), then if the top off water contained 4 ppm chloramine, the aquarium would be boosted to 0.08 ppm every day. That level appears to be well above the danger zone for many invertebrates.”
Suppose my 75 gal tank actually holds 65 gal of water. 2% of that would be 1.3 gal. If the article I quoted is correct, topping off 2 gal per day would be dangerous to some fish. Doing it even once might be dangerous if the chloramine from the 2 gal stays in the tank.
I think I’ll continue to use Prime.
(I have not found any information about dangers to plants from chloramine.)
Chloramine
A couple of years ago, PVAS held a semi-annual auction and fish show in the , where some fish did not fare well in the water provided at the show, which had been treated with Prime. Andrew B. made a comment following the show to the effect that Prime may not be the most suitable product for northern Va tap water.John G wrote:I think I’ll continue to use Prime.
I use both Prime and Am-quel somewhat interchangeably, and have never lost adult fish on a water change, but have lost killifish fry and cherry shrimp in a 10 gallon tank, where I typically use Prime with 50% water changes. I can't really say whether the fry or shrimp perished on water changes, they just sort of disappeared over time. But my question is, why is it thought that Prime is a superior product to Am-Quel or other products?
T. Moran
-
Bgssamson
- Posts: 376
- Joined: Thu Jul 29, 2004 11:57 am
- Real Name: Brian Samson
- Location: Springfield, VA
John G.,John G wrote:Fairfax County does use cloramine.
Have you seen the water report from last year? we even have 10ppm of Nitrate & NitrIte of 1 ppm. I haven't tested my water since I move from Alexandria to Springfield :oops: that's why I did not know about this, but I always treat water with prime.
:wink:
-Brian
A different water treatment was used for the water at that show. The water was not treated with Prime. I lost about 10 percent of the fish I put in the show that year (I think it was four years ago).tomterp80 wrote:
A couple of years ago, PVAS held a semi-annual auction and fish show in the , where some fish did not fare well in the water provided at the show, which had been treated with Prime. Andrew B. made a comment following the show to the effect that Prime may not be the most suitable product for northern Va tap water.
