Daytime electron density irregularities in the low-latitude F region are leftovers from nighttime plasma bubbles. Observations show that daytime irregularities are linked to nighttime bubbles and are moved by the ionosphere's vertical motion. The distribution of irregularities is similar in both day and night, with daytime irregularities spreading over wider latitudes. The pattern of daytime irregularities matches the plasma density and vertical plasma velocity patterns. This suggests that daytime irregularities are influenced by nighttime bubbles and the ionospheric fountain process.