no3 and po4 read zero. po4 always has. no3 was never higher than 15 and that was when i cut back the food 5 months ago and has read zero ever since. the chaeto grows pretty fast tho and could b why readings are zero? as for the kids, they know not to touch it. something dead maybe, nothing that i can see (altho i havnt seen in my tank for a week). maybe a very small hitchhiker mushroom? or a small duster worm? nothing i dont think my system couldnt handle?