Saltwater Aquarium Water Testing Log

Alkalinity did not kill the coral. The swing did.

A reef holds fine at 7.5 dKH and fine at 9.0. What it will not survive is travelling between the two over a weekend. One reading tells you almost nothing. A line tells you everything.

This log is built to draw that line: every test, every dose, and a full page each month to plot alkalinity day by day and see the shape of it.

WHAT IS INSIDE

• 52 weekly test pages with three test slots each, which is the cadence a reef actually needs: temperature, salinity, pH, alkalinity, calcium, magnesium, nitrate and phosphate
• Monthly alkalinity trend charts, ruled from 6.5 to 11.5 dKH across 31 days, so a drift becomes visible before it becomes damage
• Target ranges printed on every page for FOWLR, mixed reef, SPS dominant and softies
• Dosing log with alkalinity before and after, so you learn your own tank's daily consumption instead of guessing it
• ICP lab panel pages for copper, aluminium, tin, iodine and the other elements home kits cannot see
• A corrections log: one change at a time, with what actually happened written down two weeks later
• Test kit and calibration records, because old reagents lie and a changed reading is not always a changed tank
• Two full tank profiles, for a display and a frag system

The reference pages say the things most logbooks get wrong. Nitrate and phosphate at zero is not a clean tank, it is a starving one. Magnesium below 1250 makes alkalinity impossible to hold no matter how much you dose. Low pH is usually the air in the room, not the water in the tank.

SPECIFICATIONS
Large 8.5 x 11 inch format, 108 pages, undated so you can start on any Tuesday and pause when life gets busy.

For the reef keeper who already owns the test kits and wants to stop guessing.