Cecil,
One thing to watch out for is low pH. Iron oxidation is very slow at low pH, especially less than 6.0. I helped out some buddies who have well water at their camp with high iron and low pH (~5.5). We added a pressure tank filled with calcite prior to the oxidation step - worked out well. The added alkalinity and hardness should be good for fish I think. The calcite (or limestone chips) go away over time and need to be replaced.
Dale
