Your rainwater tank during the moss removal
By the Toiture Wash team · Updated on 20 October 2026 · 2 min read
Short answer. During a moss removal, the cleaning water laden with moss and debris, and then the treatment product, must not end up in your tank. The downpipes that feed it must therefore be disconnected or diverted during the job, and not reconnected straight after the treatment: the right moment depends on the product applied. Mention your tank in your quote request: the form asks about it.
Why protect the tank
- Debris: moss, lichen, dust and tile particles loosened by the cleaning run down with the water and settle at the bottom of the tank.
- The treatment product: a water repellent or an anti-moss product is meant to stay on the roof, not to be stored in the water that supplies your toilets, your washing machine or your garden watering.
- Filters: a sudden arrival of sludge clogs the filter and the pump.
Protecting the tank, step by step
- Locate the downpipes that feed the tank.
- Disconnect or divert these downpipes so that the water goes to the sewer or the garden during the job.
- Remove the moss, rinse, treat the roof.
- Wait before reconnecting: the right moment depends on the treatment product applied.
- Reconnect the downpipes.
What you can prepare
- Note where the tank is and which downpipes lead into it.
- Tell us if you have a filter or a pump: they may need to be switched off during the job.
Frequently asked questions
Does the tank need to be emptied before the moss removal?
No, if the downpipes are properly disconnected: nothing from the job reaches the stored water.
My tank is buried and I cannot see where the water comes in: is that a problem?
No: the downpipes can be located from the outside, and the inspection chamber or the overflow often shows the path of the water.