Flushes + Leaches

A flushing agent strips excess fertilizer salts from the root zone so plants can take up water and nutrients cleanly again. Pick Clearex, FloraKleen or X Nutrients to leach salts mid-cycle, a finisher like Carboflush or Final Flush before harvest, and TrueFlo to clean the lines.

18 products

Flushes + Leaches

Flushing Agents for Plants: Salt Leaches, Final Flushes and Line Cleaners

A flushing agent clears built-up fertilizer salts from the root zone and media. Growers use one mid-cycle when runoff EC climbs, or in the last days before harvest. This collection covers Botanicare Clearex, General Hydroponics FloraKleen, X Nutrients, Grotek Final Flush and FoxFarm Sledge Hammer. Finishers and line cleaners round it out....

Flushing agent infographic: salt leach, final flush, finisher and line cleaner types, label rates and when to use each

After a flush, reset the feed with our pH up and down and check runoff again. Base feeds and boosters live in the wider nutrients range.

Types of Flushes and Leaches

Salt Leaching Solutions

Clearex is an isotonic drench that lifts salts out of soil, coco, rockwool and hydro media. Botanicare says it protects cell turgor where a water-only flush can stress roots. FloraKleen runs alone, with no base nutrients in the tank. X Nutrients mixes at 15 mL per gallon.

Final Flushes and Finishers

Grotek Final Flush, made with potassium sorbate and citric acid, is labeled for the final week. Lotus Carboflush is 0-0-12 and replaces the base feed in weeks seven and eight. Athena Fade is nitrogen free and goes in at 10 to 16 mL per gallon for the last 3 weeks.

Root Rinses and Line Cleaners

FoxFarm Sledge Hammer uses yucca saponin to help water move through soil and soilless mixes. Athena Cleanse rinses the root zone. General Hydroponics TrueFlo uses hypochlorous acid to clear scale and biofilm from lines, emitters and reservoirs.

How Growers Use Flushing Agents

Watch runoff EC. When it climbs well above your feed, or leaf tips burn, run a leaching solution and then return to the normal feed. Before harvest, follow the finisher label for timing, such as Carboflush in weeks seven and eight. Always follow the label.

Frequently Asked Questions

How long to flush plants before harvest?

It depends on the product. Grotek labels Final Flush for the last week, and Lotus runs Carboflush for the final two weeks. Athena uses Fade for the last 3 weeks of flower. Pick one approach, follow its label, and keep checking runoff EC as you go.

Should I flush my plants every day?

No. Flushing is a reset, not a daily routine. Botanicare suggests running Clearex when runoff EC spikes, after heavy feeding, or when plants show lockout or tip burn. Between flushes, feed normally, check runoff EC with each feed, and keep it close to what goes in.

How do you flush hydroponic plants?

Drain the reservoir, refill with clean water and a clearing agent, and circulate it through the system before draining again. X Nutrients follows that drain, dose and circulate routine, and FloraKleen must run without base nutrients. Then clean the lines with TrueFlo before the next crop.