The direct answer for minnows in a storm
A white cloud mountain minnow stays calm through thunder and household emergencies when its tank offers deep cover, a lid with no escape gaps, and a lighting pattern that refuses to react to the weather. Storm stress for this small cool-water fish arrives as vibration and flashing, not sound itself, so your job is to soften both: plants to vanish into, steady light, and a room that stays as ordinary as you can keep it while the emergency unfolds outside.
What a storm feels like from inside the tank
A white cloud mountain minnow evolved in cool, vegetated streams and reads the world through movement sensed along its body. Thunder arrives as pressure shuddering through the stand and water, lightning flickers through glass like a giant shadow passing, and a household reacting to the storm adds slamming doors, raised voices, and torches sweeping the room. A startled minnow darts, and a darting minnow near the surface can leave the tank entirely — most storm losses in this species are jumpers through lid gaps, not fish frightened to death.
Cover and lid work before the weather hits
Plant the white cloud minnows' tank generously — fine-leaved stems, mossy wood, or floating plants that break the surface into sheltered patches — because a school that can scatter into cover settles in seconds, while one in open water keeps racing. Audit the lid the way a minnow would: check the feeding hatch, the filter cutout, and any warped corner, and cover gaps with a fine mesh or a fitted offcut. Keep a battery air pump within reach in case the storm takes the power, since a still, dark tank after a cut adds oxygen stress on top of the fright.
Conduct during thunder and loud emergencies
While the storm is overhead, leave the white cloud minnows' light on its timer even if lightning is flashing; switching the tank bright at midnight to 'check on them' adds the biggest flash of all. Stay out of the tank — no netting, rearranging, or emergency water changes mid-storm unless equipment has actually failed. Feed nothing until the weather passes, because an unsettled school ignores food and the leftovers foul the water you may be unable to filter if the power drops. Speak and move normally near the tank rather than gathering the family around it to watch the fish react.
Settling the school afterwards
When the noise ends, a recovering white cloud school regroups in open water within the hour, males flashing their fins at each other as normal order returns. Check the floor around the tank for any jumper, confirm the filter restarted after any power flicker, and offer a small feed once the school is patrolling calmly. A minnow that stays isolated in the plants, breathes rapidly in still, aerated water, or shows damage from a dash against the glass deserves a quiet, dim day and, if it does not improve, advice from an aquatic veterinarian. Asking KinsLe's Kinny what to check next during the next storm keeps the whole routine — cover, lid, battery pump, patience — attached to your minnows' profile where it is easy to find in the dark.