I got a Shubunkin Goldfish and a Fantail Goldfish a couple of days ago. They are really little right now and in a 5 gallon tank. (I've googled and realize that this is very small) at first they were very inactive they laid at the bottom of the tank and wouldn't eat. Now my fantail eats but my shubunkin usually spits it out. They both had white strings hanging off of them then they fell off and now my shubunkin has one. They are now gulping for air at the surface. I checked pH Niatrate Nitrite Hardness and alkalinity and they were all normal except hardness which was at 150. I think it's also relevant to note that I have a filter and had a rosy red that died the first day in the tank. Please help! I'm afraid the others might die too. I added a picture. I hope it came out