Odd Lumps On Tail Fin, Any Ideas?

Hi, I was wondering if anyone could help identify these lumps that have appeared on "Bob". They came rather suddenly a couple of days ago.

Bob hasn't been perfect ever since I got "him", I think he has some serious congenital defects as he has a wonky mouth, bent spine and has occasional trouble with his swim bladder.

He has recently had a couple of days in a bowl to stop his tank mates getting him during a sinking session and I was wondering if maybe he has suffered some trauma to the tail during the switch between tanks?

When you read my tank details below, some of you may feel a little disturbed at the lack of size for the quantity of my fish, but unfortunately I am one of those who knew nothing much about fish keeping (did regular water changes, dechlorinated the water, knew to rinse in filters in tank water) due to listening to the wonderful advice of your 'fave' pet shop, "how many fish you got already? Oh you'll be right with another." But I started to realise their tank just was not big enough and have now invested in a 180litre tank.

I had never tested the water quality, I wasn't aware that I needed to.

I bought some test strips (Ammonia, Nitrite and Nitrate) to set up the new tank with and have now ordered (awaiting delivery) the one recommended by you lot after reading that strips are useless!

I have started to move my fish over to the new tank after using a piece of media from my old tank to get the good bacteria going and have been monitoring the water daily- 0 Nitrites, <20 Nitates, 0 Ammonia, 2 goldfish in. Done this to get them out of the poisonous water sooner, lessen the load on the others.



Size of aquarium/pond - 35 litres
Types of fish - comets and common goldfish and 1 butterfly plec.
Number of fish and sizes - 3 comets 3 1/2" each, 1 common goldfish 3" and little plec 2" not including tails, is that how you measure them?
Filtration used and how do you clean it and how often - Elite stingray 10, sponge cleaned in gravel syphoned tank water once a week.
How much in the way of water changes and how often -- 30-40% once a week.
Do you dechlorinate - yes.
Symptoms of sick fish ie, spots, behaviour, etc - has white lumps on tail fin which have kinked the tail out. feeding normally.
How long has the fish been sick and which medications are your currently using or recently used - 2 or 3 days, not used.
Test results for ammonia, nitrite, nitrate and ph both from the tap and tank - Ammonia 0, Nitrite 0, Nitrate 160 don't have test for ph yet. will add when able.
Anything else you need us to know - history of poorly fish written in text above, had him for 2 years now.

2 of the comets in the list above now in the new tank.

Please ask if there is anything else you would like to know to be able to help me with this.

Thanks

The fish looks as though it may have Lymphocystis which is a infectious viral disease. I would personally remove the fish from the aquarium, place it in a quarantine tank and start appropriate treatment. At some point the white pimples may burst and be released into the water causing fish of similar species to also catch the viral infection.

According to the company 'Waterlife' treatment involves: "To carefully trim the fin and dab it afterwards with 'MYXAZIN' to prevent secondary infection".

The cramped conditions of the original tank have probably stressed the fish resulting in decreased immunity from forming such infections.

it is looking like a viral disease. as mentioned above if the cysts burst it can be transferred to fish in related genus'. but unlikely to cause death to the fish. think of it as fish herpes. unsightly yes, deadly, usually not.
it doesnt help that he is a weak little Bob to begin with
best of luck

Thanks for your replies, I shall see what I can get hold of and start treatment asap.