Three golds when added also put
that tank in the official OVERSTOCK category....
cloudiness is ALSO a sign of an overstocked tank. And it will take longer to stablize.
Golds require a minimum of 10 gallons per fish! 15ea is preferred by most serious keepers. You may get away with half of that if they are still small (under 3 inches) or you change you water every OTHER day. Especially since you have big fish in sharks adn plecos.
Golds require more pristine and harder water for health and coloration. Certain times in development , you might want warmer water to contol color patterning and general shape, but golds really need water that is stable BELOW 75.
The fish must be separated.....most type plecos are bad news for gold fish as they get larger. They have a bad habit of sticking to the side to suck of the slime coat off. This stresses them and opens them up to ever-present opportunistic bacterias.
Oxygen depletion may stunt thier growth, but with the smaller size comes disfigured internal organs and falling ill easy and likely spreading something through the tank with their demise.
And I believe sharks need more space to stay peaceful, and golds definitely need more space for surface requirements. In the current set up, I will be surprised if the tank stays stable for more than 30 days straight at a time (as each growth spurt unbalances the parameters). Work out the inches..most of your fish should hit full size pretty fast except the pleco maybe.
Sorry to say it but the tank owner's fish should stay and the rest get a tank of their own. Or arrange start sharing in the water change schedule that will need stepping up for the sake of the fish vitality (cheaper than treating from a disease cropping up). I know it is always a bummer to hear that ones seeming empty tank is almost overfull...but rivers, swamps and lakes are ever-replenishing and dont have that many animals /gallon either. And have A billion times better bio filter !
ps:next time she throws in the golds, if the tank is yours? ask"Are they to be feeder fish now? Don't you like em anymore? My pleco will appreciate it ^_^, Thanks!" 8O
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