Sooo... My Daughter moved to japan and left us with her comet goldfish, a black moor, and a pleco, 3",1.5", and 3". They're currently in a 5gal tank. Just got the API kit ( fish acting oddly lately) and ammonia is 8+ ppm, Ph 6.0, nitrites .5-1, nitrates 160. We had figured they needed a larger...