Im new to the saltwater tank hobby and just started with an 8 gal. biocube. Cycled for 1 week using LR and 2 days ago added a cleanup crew consisting of 3 snails, 3 hermit crabs, and one fire shrimp. The pet store guy said i could get a coral so i picked a cup coral. I fed them 1/2 cube mysis shrimp yesterday and noticed an ammonia spike shortly thereafter. It is reading between 1.0 and 1.5. Done (2) 20 % water changes Nitrite levels are ok so far. Any thing to be worried about? Any advice??