fancy goldfish

Question
hi, my fish has been happy for the last two weeks, he's in a bi-orb, for the last couple of days hes been a very different character, hes spent loads of time in the weed and today was very slow at feeding, hes not the same fish!

Answer
Good evening Trevor, thank you for your question.

Even though the BiOrb seems to be targeted for goldfish keepers looking for a "high tech bowl", the major shortcomings of the product design make this a difficult tank to maintain clean and keep stable.

There are certainly better kinds of aquariums to house a goldfish in! A rectangular tank has much more surface area than a circular tank (such as yours) of the same volume.

To compensate for this, do water changes 2-3 times a week. A goldfish is a messy fish, who will eat greedily (or is supposed to)...and there will be plenty of the "end product", I assure you! Vacuum the gravel with a gravel vac once a week, and keep that filter clean by rinsing it in aquarium water once or twice a week. Replace it regularly, I believe it is a disposable kind. Most importantly, do not skimp on the water changes. 3x 10% water changes or 2x 15-20% water changes weekly will perk your goldie right up.

A water test kit measuring ammonia and nitrite (*always* 0 ppm in a healthy, cycled tank!) and nitrate (should be kept below 20 ppm) will give you an idea of your water quality. Whatever you do, do not add any tankmates. Goldfish do just fine alone, and two goldfish would just be too many. Instead of one reasonably happy goldfish, you will just end up with two sick and miserable ones in the long run.

I hope that helps, have a good day!
Nicole

PS: A couple of sites I always recommend to goldfish owners:
http://www.kokosgoldfish.com
http://www.goldfishparadise.com