Possible high iron levels

[teadragon]

Last semester, I made the switch to a sand substrate for my axolotls' tank. Since upkeep for the sand is a tad more difficult than for the bare bottom, I stored the sand during my winter holiday while someone else was taking care of the tank. Unfortunately, I stored the wet sand in a metal container. It was all dry by the time I got back from break, but a small amount looks like it's held to the bottom of the container by rust.

What I'm wondering is whether it's likely that the sand will create high iron levels in the tank, whether or not that's bad, and if so, whether I should treat the rest of the sand. I didn't try to get out any of the sand that was stuck. I rinsed all the loose sand and have it in the tank now. I've done a 50% water change and I've had the filter going overnight. From here, the water looks colorless, but when I took some out in a clear class bowl it looked as though it might have a yellowish tinge.

Thoughts?

ETA: The sand was rust-colored to start, so I can't check it for color change due to rust.

 

[oceanblue]

I don't think there is too much to worry about. Iron in ferric form is not particularly toxic. It is ferrous iron, usually present in anoxic acid water from iron bearing strata as ferrous sulphate which oxidises to a sludge on fishes (and presumably axolotl's) gills which is toxic. If you aerate the tank for a day or two the dissolved iron levels will be non toxic at usual aquarium pH levels. Low levels of iron are beneficial to plant growth and an essential mineral for axolotls.