Two pots standing beside one another can have different moisture requirements. Treating both as 'plants that like water' removes the detail needed to care for them well.
Identify each plant and understand the growing system it is in. A potting mix, a water-growing arrangement and a marginal planting are not interchangeable situations.
Check each container separately
Look at the medium, drainage, root space and position. One plant may have a small root ball in a large pot while its neighbour has filled a shallow container. They will not necessarily dry at the same rate.
If a plant wilts, inspect its root environment before adding water. Wet roots and dry roots can both accompany an unhappy-looking top, for different reasons.
Keep a separate note for each plant when adjusting the routine. A shared shelf is a useful place to display them, not proof that they should receive identical treatment. If their requirements are difficult to meet together, changing the arrangement may be easier than trying to find one compromise routine that suits neither particularly well.
NC Extension’s peace-lily profile specifies moist conditions with good drainage. It is not guidance for an unidentified coinwort or a water-growing system. Confirm what the second plant is before transferring a watering instruction between the two.
Related reading: Peace Lily, Pelargonium and Coinwort: Common Care Problems.