Product review (3 stars): Short lived wicks - a necessary evil
{NOTE: the Holmes HWF100 and Bionaire BWF100 are interchangeable}

I bought a bionaire humidifier that uses 2 of these wicks.  They're a necessary evil, because the humidifer won't work without them.

My humidifier (a Bionaire BCM645) is basically a glorified self-refilling water bowl, with a pair of wicks dangling down into the water in the lower backside of the unit ... the wicks absorb water upwards, and the humidifier (basically a vertical tube with an exhause fan up up equipped with a humidistat) draws airflow in crosswise through the body of the wicks down below in order to blow humidified air out the top ... it's a simple design that sorta works.

The problem is that mineral deposits build up in these glorified (and overpriced) sponges, and they lose their ability to wick water upwards fast enough to keep up with the rate of evaporation ... the result is that they become dried out and crusty (and slowly stained with mildew), and only stay wet on the part that's dipped in the water.

Now, here's the annoying part, and why I only gave this product 3 of 5 stars ... they're needlessly fragile by design.  The manufacturer WANTS you to keep reguloarly buying replacement sponges, just like inkjet printer manufacturers want to keep selling you overpriced ink cartridges.  Even though I have fairly soft water, and use a carbon block filter, these wicks only seem to last me about 2 weeks per pair, by default, before they lose their ability to absorb/wick moisture and/or fall apart.  Perhaps someday someone will make longer-lasting reuseable cloth replacement filters, but as of this writing, there don't appear to be any available ... because it's against the manufacturer's fiscal interests to make and sell such.

You can save money 2 ways:

1) SHOP AROUND:  you can save as much as 50% by shopping around for the cheapest supplier, and scoffing at any implied manufacturer product loyalty.  How ?  The replacement filters for Holmes (HWF100) and Bionaire (BWF100) are functionally identical and interchangeable.  They come 6 to a package (3 pairs).

2) RINSING: These wicks are rather fragile - resist the urge to wring them out when rinsing them, or you'll damage them. Instead, fill a sink with body-temperature water, let them soak for 5-10 mins (to let the deposits soften & par-dissolve), then gently press them flat (while submerged) a few times. Then drain them (dont wring them) and reinstall. That should extend their performance by another week or so. Each subsequent rinse will yeild only half the benefit though.  At best, you'll be able to double their lifespan.

Bottom line: I don't really recommend these wicks ... but if your humidifier requires them, there isn't much choice.  However, if you use the tips I listed above, you can save up to half the cost, and make them last as much as twice as long.