diff -r 288ed828d11a -r 810569bfa16b src/EditProductTab8.cpp
--- a/src/EditProductTab8.cpp	Tue Jun 11 15:51:17 2024 +0200
+++ b/src/EditProductTab8.cpp	Tue Jun 11 16:47:11 2024 +0200
@@ -542,7 +542,7 @@
 	ui->wb_clEdit->setStyleSheet("background-color: red");
 	ui->wb_so4Edit->setStyleSheet("background-color: red");
     }
-    ui->wb_phEdit->setStyleSheet((ph < 5.2 || ph > 5.61) ? "background-color: red":"background-color: green");
+    ui->wb_phEdit->setStyleSheet((ph < 5.0 || ph > 5.51) ? "background-color: red":"background-color: green");
     ui->wb_hco3Edit->setStyleSheet((bicarbonate > 250) ? "background-color: red":"background-color: green");
     ui->wb_caco3Edit->setStyleSheet((bicarbonate > 250) ? "background-color: red":"background-color: green");
 }
@@ -722,6 +722,7 @@
         ph = product->sparge_ph;
         volume = product->sparge_volume;
 	ui->wx_phEdit->setToolTip(tr("Sparge pH should be between 5.6 and 5.8."));
+	ui->wx_phEdit->setStyleSheet((ph < 5.6 || ph > 5.81) ? "background-color: red":"background-color: green");
     } else {
 	ui->wx_Select->setText(tr("Treated Mash Water"));
 	calcium = product->wb_calcium;
@@ -733,6 +734,7 @@
 	ph = product->wb_ph;
 	volume = product->wg_amount;
 	ui->wx_phEdit->setToolTip(tr("Mash pH should be between 5.2 and 5.6. Use 5.2 for light and 5.5 for dark beers."));
+	ui->wx_phEdit->setStyleSheet((ph < 5.2 || ph > 5.61) ? "background-color: red":"background-color: green");
     }
 
     bicarbonate = Utils::Bicarbonate(total_alkalinity, ph);
@@ -766,7 +768,6 @@
         ui->wx_clEdit->setStyleSheet("background-color: red");
         ui->wx_so4Edit->setStyleSheet("background-color: red");
     }
-    ui->wx_phEdit->setStyleSheet((ph < 5.2 || ph > 5.61) ? "background-color: red":"background-color: green");
     ui->wx_hco3Edit->setStyleSheet((bicarbonate > 250) ? "background-color: red":"background-color: green");
     ui->wx_caco3Edit->setStyleSheet((bicarbonate > 250) ? "background-color: red":"background-color: green");
 }