guppy seem easy to kepp but actually it is not. guppy is a sensitive fish but small ikan lampam is more sensitive. 10% of the water condition is not good, surely died. but guppy,i think u need a new fresh water tank first fill with other cheap local fish inside. see the condition of the fish about 3-4 days. if no fish died, remove all the fish and put all guppy inside. if the cheap local fish in there 3-4 days, there is a bubble around the surface of the water tank, that mean the water have problem oledi. pour out all the water until ur testing on the cheap local fish water condition is good, then put inside the gupy. hope this help u.