Fat Goldfish.. Problem???

Question
QUESTION: To start I have little knowledge of fish. I am caring for my grand daughters goldfish,started out with 10 feeder fish,7 fish didn't make it,I now have 1 about 7-8" long separated tail fin,doing fine.1 about 2" long short straighter tail fin, doing fine. These fish look normal,Problem is 4-5",longer tail fin fish looks fat or puffy body, waste is like fine thread hardly visible,scales look expanded.I feed them Wardley goldfish flake food 2 times daily,enough for 1-2 mins. feeding time, I use tap water 74-78 degrees ,change about every 3 weeks,I have a Penguin 150 Filter & a Whisper 400 bubble maker, I clean the filter housing & rinse the filter about once a week,I change the filter every 3-4 weeks,I also scoop out the Poop when ever visible. The fish that died were mushy, lost there tails & fins. I was told to use Melafix,I keep watching and when these fish look frayed or eyes cloudy I give them 3 days of medicine, seems to work.    My question ? (Besides needing a bigger tank.) Am I caring for them correctly & is there any thing wrong with the fat fish !(mama)

ANSWER: I will say, you are doing a great job! I would like to point out though, beneficial bacteria is crucial to the cycle and ultimately health of your aquarium. If you're cleaning the filter off once a week, you could be eliminating the beneficial bacteria to feed on what the filter has caught, bad bacteria, and otherwise food for beneficial bacteria. You must clean filters don't get me wrong, but there is such a thing as too much cleaning with any part of your aquarium. Don't. Ever completely clean any part of your tank unless you are planning on starting completely over with set up. As far as the fish's waste, it depends on how long it has been stuck hanging out so to speak. The waste will begin to dissipate the longer it is free in the water. The fish could be constipated. I normally feed all of my fish once a day, and a second feeding periodically throughout the days of the week a supplement food. Goldfish are dirty fish already, sorry, so overfeeding and the lack of cleaning gravel and changing water is a big mistake. I don't see you having that problem but, try to fast the fish for a day or 2 but no longer than that at a time. As far as the melafix goes, I rarely use it. Mardel's Maracyn medication and coppersafe are broadspectrum antibiotics that are the best in my eyes and from my experience. You don't have to remove carbon like most other meds require of you. How are the water parameters? I use quick dip test strips, and I recommend you do too. See if any of the levels are unsafe. It sounds like there was a parasitic outbreak in the aquarium which led to a weakened immune system, which led to bacterial disease and death. If the fat fish doesn't show signs of improvement, this means it too has a bacterial infection which can be treated using the medication I suggested, but hurry to do these things, it can turn fatal if left unattended. Also, if you are only using the melafix medicine for 3 days, its never fully finishing the problem, it calls for a 7 day dosing period. That would be like us receiving a 2 week dose of antibiotic and never finishing them, they aren't effective. I hope this helps, feel free to contact me again anytime. Good luck and a please don't forget to rate this answer!

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QUESTION: I got confused about; Over feeding (directions say feed 2-3 times a day)What is supplement food? " Lack of cleaning gravel & changing water is a big mistake" ??? Am I cleaning too much or not enough?   Sorry I have given the 7 day treatment. The 3 day dose is for maintaince Melafix is all natural,only a remedy for repairing fins,ulcers & open wounds. Sounds like Maracyn is a stronger medicine. Do I need it? Is the fat fish sick? Is constipation serious? Thanks Peaches  

Answer
Supplement foods are, well, a supplement added to a fish's diet to maintain a natural balance of what it would actually eat if not in captive. It is a food given in addition to its normal food you give it. Instead of just eating regular old same ole thing everyday. And yes a LACK of cleaning the gravel and tanks is a big mistake. On the same note, if you do this too much, it can also have negative results. Goldfish tend to be more "dirty" so to speak, so as long as you continue to vacuum the gravel regularly, there shouldnt be any question about that. I would say, twice a month. If you only have one fish in there and you are cleaning it like it is over stocked, it could eliminate the beneficial bacteria needed to keep the cycle ongoing. What & day treatment have you given? What brand? Maraacyn? I recommended this because nothing else has ever worked for me as good as Mardel brand medication. Melafix may work, but I would'nt use if it was me. It is for repairing damaged fins ulcers etc. It doesnt work effectively enough for me, and it most certainly will not cure your fish if it has a bacterial disease, which could be the cause of your fish abnormal distended stomach. Go back and read one more time the previous answer I have given you as well. I hope I have helped clarify this for you a little bit. Im sorry if I made it sound confusing for you. I hope this helps and good luck. IF you need any other help, feel free to contact me anytime.