Black Widow Anemones can grow to be quite large, a well-cared-for specimen can grow to be over 12 inches in diameter. Most hobbyists will purchase much smaller anemones, typically between 1-2 inches in size.
As with all invertebrates, providing pristine water conditions and a nutrient-rich diet will allow your anemone to reach a healthy size.
In an ideal environment a Black Widow Anemone can double in size over six months.
Black Widow Anemones, similar to other Bubble Tip Anemone color morphs, are fast-growing Healthy anemones will either grow or split. While splitting can be a sign of stress, it can also occur in healthy corals.
The Black Widow Anemone is recognizable by its striking combination of bright pink and red tentacles and a blue and black oral disk.
Healthy black widow anemones should have inflated tentacles and bright colors. They should not display any abnormal swelling near their mouths.
The tips of their tentacles should be rounded, giving off the "bubble" appearance seen in the Entacmaea species.