Essential reading for all owners of Biorbs and Biubes, this article co-written by Cathie and Peediepixie is a great source of information


If you’ve got a Biorb you may have been given some bad information regarding which fish they are suitable for as well as the care and maintenance routine for your Biorb.

We’ll start at the beginning : you’ve got your fishless cycle going and you’re thinking about which fish to put in your Biorb. Contrary to popular belief, Biorbs are totally unsuitable for Goldfish, (and even the makers of the Biorb now say on their website that single tails and various sorts of fancy goldfish should not be kept in them). Goldfish need at least 8 gallons (36 litres) each and can reach from 8â€� long to over 1’ depending on which type of goldfish you have. Biorbs are fine for smaller fish. If you want to leave your tank unheated you could have a small shoal of White Cloud Mountain Minnows (WCMM’s). If you have a heater you could have a small shoal of Tetras or Guppies etc. or one male Betta (with a clamp to slow down the airline). Bottom dwelling fish such as Corydoras are not suitable for your Biorb as they require fine sand like substrate so they don’t damage their barbells (sp. - barbel I think) and also as they like to root around in the substrate for food.

Biorb substrate consists of rough ‘lumps’ of rock. These supplement the filter by providing extra surface area for bacteria to grow on. It may be worth buying an extra packet of substrate to put in your tank to ensure a sufficient amount of bacteria is present. Don’t be tempted to use an alternative prettier substrate - sand or fine gravel will clog the filter, smooth pebbles will not provide enough surface area for biological filtration. Also, because of the shape of the substrate, food can easily fall through the pieces and rot underneath, when cleaning your tank be careful to remove any old food under the substrate. Goldfish like to route around in substrate searching for food and the substrate is not suitable for this. If you wish to feed peas or similar, to prevent the peas from falling between the rocks and rotting, you could place them on a small plate in the tank.

Ok, cycle is complete, you’ve added your (small) fish and now you need to think about your maintenance routine: filter cleaning etc.
You need to remove 20-25% of the water weekly to keep the water clean. Replace with fresh dechlorinated water. (You do not need to add the mystery sachets supplied with Biorb filter cartridges). You can wipe the sides of the tank with a soft sponge/cloth so as not to scratch the plastic.

Despite what the Biorb instructions tell you, when you clean your filter (once a month) you SHOULD NOT remove and throw away the entire filter cartridge as doing so will remove all of the good bacteria built up in the cycle you did. Instead, the first time you do this, tip out and throw away the black granules (carbon) and white granules (zeolite). You will not need these again unless you need to add some carbon granules in the future to remove medication. Rinse the cartridge and sponge in a bucket containing old tank water so you don’t kill off any bacteria living there, then replace. Do this every month until the sponge is in danger of falling apart, then replace half one month, half the next.

Finally, live plants are great for water quality and therefore the fish too, Unfortunately Biorb substrate and lighting are not suited to growing many aquatic plants. However, plants such as Java Fern and Anubias can be attached to rock or bogwood and have low lighting requirements. Also moss balls are floating plants with minimal effort required to grow them and are great at combating algae growth.


Written by Cathie and Kirsten (Peediepixie)