This is my first post here.
Ok here is the scenario:
Rescued 3 standard goldfish about 8 months ago who were not fed in weeks, were in a 10 gallon tank with no aeration and the HOB filter had quit...not to mention the water was green and the small tank was 25% empty (due to water evaporation).
They now live in a 30 gallon cycled tank with the following levels:
Nitrate: 40 - 50
Filtration: 1 - aquaclear 150 AND 1 - aquaclear 20 (I have both in order to keep up with the large amount of waste that goldfish produce)
Aeration: 1 powerhead with venturi (topfin 30 gallon)
I don't use any other additives to the water except for water conditioner (aquasafe). I do a 50% water change weekly and gravel is vacuumed twice a month.
Feeding is done twice a day and only enough to last a minute or 2 (I do not over feed).
So; one of the goldfish has been on the bottom of the tank all day. He will sit there for a minute or two and then frantically dart to the top of the water (for air I suspect) and then he will settle back down to the bottom for a bit and then the cycle begins again. When I come come close to the tank he gets excited like he is going to be fed. This shows me that he still has plenty of energy. When he sits on the bottom sometimes he will roll to his side (but then he corrects himself). Ever since I rescued them this fish (at night) sleeps at like a 45 degree angle with his head pointing down.
The two other fish are totally fine.
Based on all this I have to assume that he is suffering from swim bladder disease...is this assumption likely to be correct? It is my intention too let them (all three goldfish) fast for two days and then feed them peas for two days (apparently a cure of constipation and swim bladder disease).
Any guidance would be great.