Check out the airjet tubs (Bain Ultra and Aquatic). They blow air to circulate the water and then blow plain air after the sensor detects that the tub is empty to make sure no water is left standing in the system. Another thing to consider w/a whirlpool type tub is that the water may get very cold while you sit. The Aquatic tubs have a line (HotSoak) that has a heater included that helps the water stay warmer. We're actually buying an Aquatic soaking tub with a heater (not for whirlpool) Here is a link that might be useful: Aquatic HotSoak Features

l got a very prompt response from Neptune about the mould in the lines and air causing water to shoot out and up. Here is the response: The active-air jets do not have a check valve so some water will enter the jets and tubing. However, the jets/tubing are installed at an angle so that the water drains out after use. Furthermore, a drying cycle activates 20 minutes after use to clean and dry all conduits. If the tub will be used as a shower, we recommend the air system be briefly activated after each shower use to ensure the drying cycle is initiated and the tubing stays dry/clean. We have had some complaints about excessive splashing but this depends on the tub shape/form and we’ve never had such a complaint with the Wind model. We're having the Wind model installed which is why they referred to that one in the response.

I'll have to be honest, as much as I want to believe in Aquatic after talking with their incredibly enthusiastic and helpful cust srvc rep,as well as the most impressive specs on the market, I visited a showroom yesterday to experience the real deal (Infinity VII) and found the dry test-drive a bit harsh on the bones, i.e., doesn't conform to body like I had hoped, a little too upright and not conforming to the reclining torso. That test drive, albeit a dry run, convinced me this was not the tub for me despite it looking ideal on paper. Granted I wasn't able to float in the tub with water, so this is slightly unfair to the mfr, but getting in and out of the deep vessel along with reclining in the tub without water was surprisingly uncomfortable, and bone-crunching. I'm a young man still, and felt like multiple grab-bars on the walls would be de rigeur. The only reason I post this is not to discourage you from buying Aquatic, but because shopping for a whirlpool/airbath combo has been one of the most difficult quests I've experienced in planning my bath addition, and on paper, this was the tub for me, in vitro, this was NOT the tub for me. Just keep in mind that you simply must seek out a showroom to sample any tub prior to making the huge investment - not just money for the tub, but permanent plumbing specific to that tub leaves little room for future change of heart! For this reason, I've been very careful in ensuring that I'd be completely happy with the fit, and felt it necessary to share my experience. This is a decision 3 years in the making due to lack of showrooms that simply don't offer the real test drive or tub variety that gives you an overall gestalt. Again, Aquatic might be for you, but test drive it, or your regrets will eat you up. Other tubs I've crossed off the list, right or wrong, were Bain Ultra cause I simply wanted the combo, however, they seem to have an unbeatable reputation in the strictly air-bath category. Sani-jet, I actually experienced with water, and the jets were simply too weak for me, but again all their specs looked good on paper. Neptune, I experienced in a hotel, and was extremely impressed, but when it came to owning one, the contour again wasn't something I'd want to recline in for an hour, and none of this years styles/profiles appeal to me. Americh, don't know. Maax.....two trades people gave me bad reviews saying they make the most comfortable, stylish tubs with the necessary whistles and bells, but technical issues required discontinuing their carrying the line....surprising, as Home Depot Expo was pushing this on me like you know what. What am I going with, well I did a dry test run on the Jason LX635 (6 foot) which meets my comfort criteria without water, looks great on paper, has been in the business for as long as Jacuzzi has been in business (Jason=son of Jacuzzi), and was carried by a local trusty high end fixture place with exceptional reputation and attentive to customer feedback. Again, I'm taking a risk without doing a 'wet' run, and their head pillow was so poorly placed, that I dissed the option, but overall, it met most of my criteria. Will keep you posted after install, etc. The most comfortable tub I've experienced was the Maax oval-shaped whirlpool-air combo (Pearl?), but again, I talked to two vendors who said they had issues with them which is highly unfortunate since comfort-wise and on paper it was the perfect tub, like sitting in a LazyBoy, but with water massage. I hope to seek something comparable in the Jason.

Just a quick update. I spent days reading material on air tubs and whirlpools and got my decision down to a 36 x 72" Jason and Purebath. To get an outside opinion, I called an online bath dealer in the Richmond, VA area where I used to live (Whirlpooltubs.com, Steve) and after discussing a lot of models, which he sells as well, he steered me to Mansfield, an UN-fancy company that offered a ton of features and everything I was looking for, at a nice price. I ended up with the Baywood 6 Ariance GentleTouch (air bath version) which has back jets with heated neck/back rest, heated silent air (all offer this), included neck pillow, chromatherapy. This combined the features I thought my husband might benefit from (back jets) with the surround air jets, in a quiet system, as we will put the motor on the other side of the wall with insulation. Mansfield offers the Ariance in 3 models: HealthTouch (whirlpool), GentleTouch (air bath) and DualTherapy. I would love to tell you what I think about this bathtub, but we are still building our home and are months' out yet. This dealer was on the ball and very helpful.