Please Help My Fish Are Dying

[fatheadminnow]

Your welcome!

Looking forward to seeing what your levels are when the API test kit arrives.

-FHM

 

[waterdrop]

mickspark81, in reading your comments I found myself getting the feeling that you are falling a bit into the trap of thinking only of the core water tests we perform rather than picturing in your mind that the water chemistry is really more complicated. The tank water chemistry (I always think its funny that that wonderful crystal clear stuff we like to look through can have some much *stuff* in it ) is really ever changing and vastly more complicated than the simple stuff we talk about here day in and day out.

The Nitrate(NO3) test that we encourage as an indicator of how our gravel-clean-water-change is doing, is really just symbolic. It enourages us to do our water changes. But the water changes are hardly about getting the Nitrate out, instead they are all about getting all the "unknowns" out, all the "other stuff" out. There are dozens or hundreds of other things... trace metals, various inorganics, plenty of organic molecules... that in many cases will just build up and build up as the pure water evaporates that we don't want to have reach a toxic level. And evidence that they will indeed reach a toxic level abounds, its the cases we see of "old tank syndrome." In those cases the fish have become used to some unknown set of higher concentrations of substances that didn't evaporate and weren't removed and then when a water change happens for some reason, the fish suddenly die! Its just way too expensive or difficult to test and measure all these things. Over the years, Nitrate(NO3) has become the "canary in the coal mine" that warns us to keep up with our water changes, but its much better to have a healthy respect for the unknowns that go out and the good stuff like calcium and trace iron (the "nutrients" as FHM has described above) that come in during water changes.

Unfortunately though, its ultimately, for the experienced aquarist, not even as simple as the description I've attempted above as frequency and percentage of regular maintenance water changes will probably be forever debated and discussed. There are other sides to water changes. For instance there's the subject of algae. For the algae problem more water changes are good in that algae spores and even algae themselves are removed from the tank, but on the other hand the water changes can also be a source of ammonia level instability. In low-light planted tanks without pressurized CO2, the "below zero" ammonia levels are forced to fluctuate by water changes and can be the factor that triggers brown algae (from the ammonia variations perhaps) or black brush algae (from the CO2 variations brought on by the water changes) just as a couple of examples. And there are even setups like Walstad tanks where many of the goals are different and the mulm and dissolved organic carbons not being removed from the tank is considered an advantage, but that's beyond the scope of our discussion I admit.

~~waterdrop~~