Hehe, believe me, pretty much no matter what you do, someone else has done exactly the same thing, somewhere! You are not alone. I have done all kinds of weird stuff to my tanks. I think the color is from the tannins in the peat, but not completely sure.
I would suggest doing water changes until the nitrites are gone. White clouds are hardy, but it will stress them and if they had ich recently, then they do not need more stress. Salt can alleviate nitrite poisoning, but most plants hate salt. If you are worried about disturbing the substrate, then you can do the water change without doing a thorough gravel vacuuming. Just hold the siphon end above the gravel. Oh, and cut back on food if you haven't already. Eventually your plants will pick up the load, but be careful until they do.