Nitrites aren't capable of 'consuming' anything---they are a chemical, just like water, or ammonia. Several different kinds of bacteria process ammonia, nitrites, and nitrates--nitrites are a by-product of ammonia, nitrates are a by-product of nitrates.
If I recall the history of this tank, the nitrites have spiked perviously, correct? So, it seems likely that there was a recent increase in the supply of ammonia--either overfeeding, or the addition of uncured live rock, maybe? The ammonia rises as a result, and the nitrites will spike in a short while. There are critters 9ie, xenia) which will soak up nitrates, and a 0 reading isn't completely impossible, especially if you're doing water changes. IF you can identify the source of the additional ammonia, then using the ammo-chips to bring down this small spike is fine--just start with a small amount, adding until the ammo drops to ) and then remove them quickly. This way, the existing bio-bed--which can handle the normal load--isn't starved.
I do agree that you're going to have problems with the mix of fish you currently have--but I've said that before.