Depending on your systems evaporation. Will not work if too high.
Securely place a large water bottle upright in your sump lid slightly below your waterline. Filled with your
ro/
di water. After it is secured(whether by clamps, cut and bent acrylic etc... Unscrew the top.
Will act as emergency top off for a few days.
Not good for long term but could get you by if can't buy and setup an auto top off before you leave.
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