LC50s expressed as mg/L KCl added to the dilution water.

Expressed as Fg Cu++ added per liter of dilution water.

All material should be flushed or rinsed thoroughly with dilution water before using in the test.

The DO-axis intercept is oxygen depletion caused by the dilution water and should be less than 0.20 mg/L.

This is necessary because impurities in the dilution water may cause significant alterations in the results.

Expressed as mg KCl added per liter of dilution water.

USEPA (2000a) provides additional guidance on selecting appropriate dilution waters.

It is sufficient to rinse new sample containers once with dilution water before use.

For this reason, it is recommended that only approximately 10% of the test organisms be exposed initially to the dilution water.

New, disposable, plastic test chambers may have to be rinsed with dilution water before use.