Although very rare over the years we have had a number of instances where customers have reported a bad smell coming from the waterbed mattress. This is not to be confused with the smell of new vinyl at the time that new waterbed mattresses are first installed. This particular vinyl smell can be quite strong at first but fades over a few days but some people are obviously more sensitive to smells and report that it lingered for several weeks before disappearing completely.
The smell we are talking about develops some time after the water-bed mattress is filled and is described by those suffering as a stale straw smell that gets into all the bedding and is very unpleasant.
Bacteria. Bacteria is in the water when waterbed mattresses are first filled. A stronger waterbed conditioner should always be added when filling a waterbed mattress. If this was not added or the amount of bacteria in the water at the time was too much for the conditioner to cope with then the bacteria will multiply and this could cause the smell. There is an acceptable level of bacteria in tap water but you only need to do a google search for 'bacteria in tap water' to discover that all is not well with our drinking water. The smell could develop within the first six months or after several years. We have noticed that for the smell to occur after several years is often as a result of the customer not regularly adding their six monthly waterbed conditioner. We send an email reminder if you wish to sign up for that.
You will need to act fast as the smell gets worse quite rapidly as a result of the bacteria multiplying. We are not scientist but over the years and though discussions with the British Waterbed Association and many other waterbed retailers and service engineers we have developed a method to treat the mattress which has produced very good results.
You will need to use a dedicated waterbed pump which you should be able to rent from your waterbed retailer.
Completely empty the mattress until it is vacuumed flat and no more water is coming out.
Pour into the valve two litres of thin bleach and refill the mattress just above the water level. Remove as much air as you can and replace the plug and cap. Then walk all over the mattress to work the bleached water through the fiber and leave it in for at least thirty minutes. The more you squish it about the better, so get the kids on there to help. (they'll love it.)
Thoroughly empty the bleached water.
Refill the mattress, at the same time pour in a large tub of fine table salt and an 8oz first fill conditioner which is stronger than normal waterbed conditioner.
If it works, great. If it does not, the smell will come back a few weeks later even worse. Unfortunately this is not a warranty issue as it is not the mattress causing the problem but your water so you will have to hope you have been dealing with a reputable waterbed shop that will replace a mattress at a reduced price.