Extreme mould removal in carpet
Remove the affected carpet from the car, which will involve removing the seats, kick-panels, sill and side cover plates. If the mould is in the under-felt, (it usually will be), replace it with new under-felt. While everything is pulled out, have a really close inspection of the area to be 100% sure you have found where the water has been coming from. Fix the issue (or issues) and then thoroughly wipe clean the exposed bare floor with Fabra Cadabra (yep, it's good at cleaning many hard surfaces as well), steam clean the carpet, then spray it with our Anti Mould product (only available online, not yet sold in stores) and leave to dry (around 30 minutes on a summers day). While it's drying, spray Pong-Go in all cracks and recesses in the cars' interior, then both sides of the dry carpet and then leave it all to dry for a day or two in the sun. Smell the carpet before reinstalling; if you can smell or see any mould, it might be best to replace the carpet as well. Mould spores are difficult to kill off, let alone clean from dense matter like carpet, so it can be best to replace it depending how bad the mould infestation is. After making that decision, you can look forward to the fun job of putting it all back (with the new under-felt) in the car. Spray with Pong-Go into the fabric trim and carpet after it's back in the car and you are done. Now make sure you closely monitor for any potential new leaks in the cars' cabin and deal with fixing them ASAP.