My love of goldfish started when I was given Mr Sharky by a close friend in a childs starter tank, He didn't live long as he had been kept in bad conditions I had him for a year we bought him a new home & some friends Basil & Jaffa I was heartbroken when I lost him.

His friends lived in a 64 litre fish box tank with a bar filter, I regulary test the water with my test kit & everything was fine, I do weekly water changes & they had a flake, frozen food diet & when the winters were bad I put a heater in the tank not to high as our flat was freezing & was concerned for them. When Sharky went I bought Thor to add to them, they lived happily together for 3 1/2 years when something went totally wrong in my tank. I came home from work & there was Jaffa dead no warning signs nothing he had been totally fine feeding etc. We did a water change added some fish safe & monitored the tank testing the levels etc. Then a week later Thor developed a massive lump on his side concerned I rung a trusted local aquatic shop for advice, I took Thor into them to check him over & was told he had worms burrowing out of him it was not nice for him & was given myaxin? to treat the tank, gradually as the weeks went on he got worse & worse we did all we could until finally when I was away on holidays & my dad was caring from them he died with only Basil left who was my smallest,he had been kept in an overcrowded tank full of bigger fish who bullied him before i rescued him he hardly grew & had a bent tail poor fishy. When I got back from holidays I was devasted to find Basil under the filter gone my Dad had informed me he had been feeding fine etc. Upon testing the levels the P.H had dropped to 6.4 & the Nitrate had spiked to 80ppm!, the Nitrite was 0ppm & the Ammonia was 0.25ppm. We changed the water & bought a P.H booster for the tank but to no avail the P.H just won't go up. We now have 8 black widow tetras living together in this tank who are doing fine.

We also have a 48 litre tank with 3 cherry barbs,2 peach danioes & 2 goldfish Atlantis & Tandy & 1 loach Phil who have lived together fine for over a year & have grown & were thinking of moving all these into the 64 litre tank once the problems are ironed out & moving the tetras into the 48 litre tank & buying some platties to add some colour, but after reading so many posts I am starting to think I am useless at fishkeeping & that I am responsible for what has happened at one point I was considering selling everything & giving up.

Any advice on swapping the tanks around would be appreciated & some pointers on where I am going wrong would be great as I am devastated by what has happened recently.

Thanks for reading my post :)

I'm afraid you have been overstocking a little bit. The tetras should have a minimum of 70l so it wouldn't be a good idea to move them to the 48l. The PH not rising is worrying, have you tested the test kit your using? What reading does it give on your tap water? Also how much of the water did you change?

The goldies would very much appreciate a larger tank. Have a look at the tail of four goldfish thread. linkyThe recommended tank size would be 140l for the first goldy and 45l for each fish after that. They would also benefit from an oversized filter.

My tap water P.H is 7.5 & I have been doing 50% water changes, & still to no avail. After reading what you have posted I am now thinking of selling my 64 litre tank & re homing the tetras to give them a better chance, & buying a bigger 200 litre plus tank for my goldies to give them a nice new home :D Xx

When you tested your pH and found it to be 7.5 was that straight out of the tap, or after it has stoodfor 24 hours? Water companies often put additives in to adjust the pH and taste and these take time to evaporate, and the pH can often change quite a bit.

As your nitrate rose quite a lot what I suspect may have happened is that you didn't do enough water changes, and the buffering capacity of your water was exhausted.

I would keep the Tetras in the 64L tank. its about the right size for them, and if your water naturally falls to a pH under 7 it will be ideal for them. (Platies won't like the soft acidic water however, and you'd be pretty much fully ) The 48L tak is, unfortunately, totally unsuitable for any of the fish you have in it, and the mix of fish you have is largely incompatible. You will need to think about which fish you want to keep, and stock your tank(s) accordingly.

Fancy goldfish need a tank of 150L or so for the first one, and another 50L for each goldfish thereafter. Common goldfish really ought to be in a pond.

Weather Loaches need a tank at least 4' long, and ideally about 2' wide, which works out at 300L or so, they're bottom-dwellers so need something wide rather than tall. They're sociable fish, so you need at least 3.

"Peach" danios (Do you mean "Pearl" danios?) are fast-swmming active fish that need a tank about 3' long, and do best in shoals of 6+ (the more the merrier). They're small enough (5cm, and slim bodied) that a big goldfish will see them as lunch, although how easy they'd be to catch is another matter). I'd rehome them if I were you, as they prefer cooler water, so you couldn't mix them with the barbs and tetras, although they'd be good in a shoal with the loaches in a nice big tank. (I keep loaches and White Cloud Mountain Minnows together).

Cherry Barbs are tropical and like it much warmer than either the Danios or Goldies. They'd mix with the tetras, but you need a larger group (6 or more), and I think that would put you overstocked, so I'd either rehome them and keep the tetras, or buy more and move the tetras on (keep whichver fish you like the most).

Keep the 48L as a quarantine or hospital tank for the smaller fish (I keep a wodge of filter sponge in an external so I can pull it out and set up a QT if necessary.)