Want to keep something in your coldwater aquarium besides just the fish? Jeremy Gay takes a look at your choices.
For indoor, coldwater aquariums choose Apple snails or Physa snails, which you usually get free as a pest species on live plants.
For temperate aquariums, of 18°C/64°F and above, virtually any of the myriad of new shrimp and snails available for tropicals will also be fine. However, you need to mix them with great care, as many fish will look upon them as food.
Avoid mussels and clams, which are hard to feed and could decompose in the tank, and steer well clear of any crayfish you spot.
There's only one legal crayfish in the UK - the Red-claw, Cherax quadricarinatus - but illegal ones are sometimes imported and sold unknowingly from time to time.
Crayfish are very predatory and will snaffle most fish, so they're really only suitable and safe in species tanks.
For ponds and colder tanks choose Stagnalis snails and Ramshorn snails, which are available outside in water garden centres. Ramshorns are more plant friendly than Stagnalis.
This item was first published in the September 2009 issue of Practical Fishkeeping magazine. It may not be reproduced without written permission.