Fri evening I did a water change and treated for an algae bloom, Sat morning both goldfish where fine. Sat night one of the goldfish was floating on the top of the water and died shortly after I gave meds for a swim bladder infection. Sun morning my daughter thought the second goldfish was stuck near a rock, it did look like she was stuck so I moved the rock. Since Sun morning the fish has not swam at all, she (he?) is laying at the bottom of the tank. She'll wiggle around a bit to move some but has not come off the rocks since Sun. While looking at her today it appears her fin is split (pectoral fin) into 3. There is another goldfish in the tank (I bought him Sat evening when I treated the other one as these are my children's pets and he replaced the sick/dying Nemo) and the new fish is fine isn't sick at all. I did a partial change yesterday (about 25%) but didn't want to do too big of a change and stress the sick fish out. What can I do? She's barely eating anything compared to what she normally does, she's just searching the bottom of the tank for food. I'm unsure as to nitrate etc...levels and plan to take some water from the tank in tomorrow to have it checked, i have nothing to check it with. Have had the fish since Feb and have never had a problem with the tank until we got the algae bloom. It is a 10 gallon tank and the filter is running fine.
10g is too small for a single goldfish, let alone two goldfish. Adding algaecide then adding another med likely resulted in a lethal combo chemicals. Start changing 50% of the water daily with temperature matched, properly conditioned water until you can figure out your stocking situation. Depending on the type of goldfish, you will need a 30+g for two fancies to much bigger if they are single tail goldfish. Please read this link for more information on goldfish & their care:
thank you for your reply, the fish was dead this morning. i was under the impression that they would be fine in a 10 gallon tank for at least a year as that i found while researching the fish before buying them? they are fancy tail goldfish and from what i read they would be fine for about a year before i would need to put them in a larger tank.
If they were babies when you purchased them, they should be growing at a rate of 1/2in to 1 inch a month. Not having sufficient water results in stunted growth. Stunting is not 'curable' and will result in health problems & premature demise. Its easily preventable by having sufficient water from day 1. Goldfish do the majority of their growth in their first 2-3 years of life so its important to have lots of water, adequate filtration & lots of big water changes. Please ask any questions you may have!