Planorbis planorbis is a species of air-breathing freshwater snail, an aquatic gastropod mollusk in the family Planorbidae, the ram’s horn snails. This species is widely distributed across the Palearctic region, and is found south of Oslo in Norway and across Europe to parts of North Africa; it is also found as far east as Lake Baikal, Russia. The habitat of this species is shallow standing and slowly running freshwaters on a mud substrate, also ponds and temporarily drying flood waters, up to 1 metre depth. Planorbis planorbis does not tolerate intensive water movements but is tolerant to eutrophic conditions.
This species, like all planorbids, has a sinistral shell. The width of the shell is 10 – 20 mm, height 2.5 – 4 mm. The keel on the periphery of the shell is near the edge closest to the spire side, which is carried downwards in life. A rather thick and strong shell. It is not glossy and it has a paler keel towards the upper part of the periphery, above the mid-line. There are 5 or 6 whorls which increase regularly in size. The mouth may be slightly expanded and sometimes bears a narrow rib inside.
Planorbis planorbis can be an interesting addition to a community tank. These snails can be a good match for species tanks as well, like shrimp or snail tanks. Planorbis planorbis can do a good job keeping a tank clean by eating uneaten food, dead or decaying plant matter, debris, detritus, and soft algae build-up on hard surfaces. This snail can be seen for hours on end canvasing the tank for edible matter.
Planorbis planorbis can do well in nearly any size tank, from small tanks like 5 or 10 litres setups to much larger ones, provided the rules regarding fish count are followed. Although a Dwarf Flat Ramshorn snail is not the escape artist like some other snails are, its best to keep the tank covered to the extent possible.
Planorbis planorbis can adapt to a variety of habitats, but they seem to really enjoy tanks with a variety of live plants. Live aquarium plants shed dead or dying plant matter into the water serving as food for the snails. Tanks with live plants are never “too clean”, making Planorbis planorbis a good custodian. A Dwarf Flat Ramshorn snail also enjoys a tank with lots of rocks, caves other interesting spots to explore.
These snails are very adaptable and can do well in a range of water conditions. Planorbis planorbis can do well in established tanks with clear, moderately moving water, as well as in tanks more on the murky side. Either way, the tank water should be well aerated and oxygenated, with stable water parameters. Planorbis planorbis do best in tanks where sudden shifts in conditions are avoided. Planorbis planorbis is a cold water species. The snails should be kept at 10°C – 25°C. Recommended pH 6.0 – 7.5 with water hardness at around 8 – 20 dGH. These snails can be kept outdoors all year round without any problems. They survive under ice during winter period.
When keeping Planorbis planorbis, it’s important to test tank water regularly. Make sure Ammonia and Nitrite levels are at 0 ppm, and control Nitrate levels as well as organic matter accumulation with regular partial water changes. As with other shelled tank mates, be very careful when using medications and plant fertilizers as some of the ingredients may be harmful. Most importantly, avoid copper. Even in small amounts, copper can be fatal.
Planorbis planorbis spend a lot of time on the hard surfaces of a tank searching for something to eat. Dwarf Flat Ramshorn snail food sources include dead or decaying plant matter, soft algae, uneaten food and fallen tank mates. Their food should also include a variety of fish flakes, pellets, bottom feeder tablets, algae wafers and calcium-rich supplements. Calcium is important for healthy shell growth. As for feeding, feed in small amounts and no more than the snails can eat in 5 minutes.
Planorbis planorbis eating a balanced diet of debris, aquarium algae, vegetables and commercial supplements will grow quickly and steadily. This is particularly true with Calcium. If Calcium levels are sufficient, a snail will grow thick, healthy, crack-free shells. If food is less plentiful, or if Calcium levels are insufficient, growth rate will be slower. Shells will be thinner with signs of small ridge-like cracks. Therefore, it’s a good idea to feed Planorbis planorbis commercial food fortified with Calcium.
While Planorbis planorbis may sometimes be interested in eating plants with soft, delicate leaves and stems, a lot has to do with the hardiness of the plant and how well the snail is otherwise fed. Keeping hardy plants with durable leaves like Anubias should not be a problem. And keeping Planorbis planorbis well fed on a diet including fresh leafy vegetables should also help reduce the chances that live plants will be eaten.
Healthy, well feed Planorbis planorbis have a lifespan of about 12 – 20 months. Some snails can live longer than that with a bit of good fortune. That said, it’s not uncommon for some Planorbis planorbis to die shortly after being added to a tank. Death may be attributable to stress during transportation or the shift in parameters between the water in the display tank and the home tank. But either way, the possibility of quick death exists and is worth a mention.
The snails lay egg clutches on hard surfaces soon after being added to a tank. The egg clutches are clear, jelly-like globs containing what appear to be about one dozen round areas, each with a little dot. These egg clutches can be most noticeable when they are laid on aquarium glass, but for every visible egg clutch, there are undoubtedly sever others hidden on other hard surfaces. After a couple of days, each little dot appears less clear and more translucent-white in color, and the shape of each baby snail can be seen. Soon thereafter, the little translucent-white snails can be observed wiggling their way out of their egg and moving away from the clutch.
Planorbis planorbis tank mates should not be aggressive fish like cichlids, goldfish or other fish that can harm a small defenceless snail.