Filtration occurs when the smoke makes contact with the water, so in order to get 100% water filtration, you need the surface area of the bubbles to be equal or greater than the surface area of the smoke. However the surface area of the smoke is many orders of magnitude greater than the surface area of the bubbles even with extremely effective and numerous percolators. Downstems are definitely the most commonly overlooked percolators.
Before other percolators entered the market, downstems were the only percolators, and they are what set water pipes aside from dry pipes. Certain pipes are considered ‘stemless’ when they don’t have a downstem that comes apart from the water pipe as a separate piece, but even stemless bongs sometimes use stem percolators. The design is very simple, there’s a tube that reaches into the water and the air has to travel through it and comes out as bubbles. Adding holes, slits, or sometimes more complex mini-percs, on the end of a stem can increase the number of bubbles and therefore their surface area, thereby increasing its percolation power. The biggest advantage to downstems as percolators is their size / mobility. Since downstems are easily removed from a bong, they can be easily cleaned or replaced as necessary. If you prefer to like to use a simple, no percolator bong, we recommend spicing it up by adding an improved downstem, and you still keep all the benefits of your simple perc-less bong while retaining the additional percolation power. Tree Percolators are among the first percolators separate from downstems used in water pipes, and there’s a lot to say about them.
If you understand its design, you understand perfectly how percolators work. There’s a tube that goes up through the middle, that tube attaches to a bunch of arms up high, and those arms descend from that attachment point into the water. This way air comes from below and is forced up through the central tube and down the arms of the perc where it enters the water as bubbles. The arms are typically diffused with at least 2-3 slits in each arm. Although they are the most common, and probably exactly what most people think of when they think of a percolator, there are a lot of problems with their design compared to other percs. Anyone who has been around bongs for awhile has seen a tree perc break. For every arm, there is a joint attaching it to that main tube mentioned above. These connections are melted together, and usually are no more than 2-3mm thick at most. Even if they are 4mm+ thick, there’s always going to be a weakest link. Furthermore, smoke always takes the path of least resistance. The tree percolator’s design means that the top slits of each arm are closer to the water’s surface and therefore experience the least resistance. This means that even though your tree percolator may have 10 slits down the side, only the top two or three actually have smoke go through them. Additionally, if your bong is tilted at all to one side, like many people do when they take a hit, one side will be closer to the surface than the other side, rendering half of the perc less effective. This can be a problem with almost all percolators to a degree, but it’s more pronounced with tree percolators. Additionally, it’s very uncommon for the slits of a tree perc to be perfectly level, so the higher slits experience less resistance thereby rendering the lower slits less effective. One important reason is visual interest, which is important to a lot of smokers. All those glass rods do look good while working in harmony. Additionally, some people like them for the nostalgic value. There was a long period of time when tree percs made up more the majority of all percolators, so some people just like them because their first bongs had tree percolators. Regardless of artistic or nostalgic value, tree percs do in fact still do their job, and do it without creating much drag, so while a tree perc isn’t inherently bad, it’s just not our favorite. Showerhead percolators go by many other names, such as UFO, tire, and others. They were one of the first percolators to come after tree percs and have a very similar design.
They use a tube that comes up through the middle from the chamber below, which is covered by a larger tube reaching down to the perc where air and smoke exits into the water as bubbles. This design can be clearly seen in the image on the left. There are many different designs, ranging from 4 slits to multiple tiers of 50-slit showerheads, as well as more artsy designs with bulging spheres in the middle to resemble flying saucer type UFOs, hence the name. They suffer similar downsides to tree percs, however since the slits are not stacked vertically, their water flow tends to be more evenly distributed. Furthermore, since they have less individual parts, they’re less prone to breaking. Showerhead percs may not be the best available, but they make an excellent improvement to downstems. It’s typical for stemless pieces to start off with a small showerhead as the first perc before the next larger perc. Although multiple showerhead percs are often stacked inside a single chamber, this makes the lower showerheads less effective because the airflow is distributed more heavily to the top showerheads. Honeycomb percolators are our favorite percs here at Stoner Pros. As disc percolators, they are small, easy to make, and take up very little vertical space.
This means they’re cheap and you can fit a lot of them into a small vertical space. Additionally, they are one solid piece with no weak spots, which is why we recommend honeycomb percs with thicker (7mm+) pieces, as having a 2mm Tree Perc inside a 9mm tube completely defeats the purpose of 9mm glass.