(the following will cover the 4 types of bowls I have owned and used. There are many more types available that I will not cover as I haven't used them)
Clay Bowl: Mostly hand-made, can be cheaply made or nicely thrown. Normally uncolored brown or red clay, sometimes glazed. Holes range in number from 3-5, normally on the larger side. I've seen them in small sizes for about 10-15g of shisha all the way up to X-large bowls great for large groups that can hold 100g of shisha. Can have a tendency to shatter after long term use (I broke mine putting it on the stem one day - sliced my hand too). Most Egyptian or lower end Hookahs come standard with these bowls.
Standard White Clay (also known as Modern or MYA): Can be hand made, mostly machine made. Normally made from white clay or porcelain. Typically color glazed, although glaze can be complete, partial or just outside only. Tend to be shallower and have a larger diameter than typical clay bowls. Holes range in number from 5-10, tending to be medium in size. Most Mod/MYA bowls can hold up to 25-35g of shisha, due to the shallowness. They also come in a style with an attached metal windscreen. Typically seen on Modern or MYA hookahs.
White Clay Dual/Tri/Quad Head Bowls: These bowls share many characteristics of standard white clay (Mod/MYA) bowl, but for one major different - they have either 2, 3, or 4 individual smaller heads for holding about 5-15gs of shisha. These bowls also come in a newer version which has 1 bowl, but is compartmentalized to hold 2-4 different types of shisha, without the need for multiple coals (which can be dangerous).
Glass bowls: I've only seen 2 major types - Pyrex and Smiley's. Typically made of glass (either clear or colored) and mouth-blown. Pryex appear to be two piece bowls, while Smiley's are 1 solid piece. This can be helpful, as due to the nature of the item, it may crack or break along the stress point (the joint) after long term use (heat expansion), but if your careful it should never happen. Smiley's come in 2 sizes and I've only seen Pyrex bowls in 1 size. Typically glass bowls have 3-4 holes, ranging in size. They are often slightly taller that normal clay bowls. The amount of shisha they can hold depends of size and packing, ranging from 15g to 40g. Smiley's glass bowls often come with a glass screen for use, but foil can be used as well.
Phunnel: Phunnels are a modified bowl. Instead of being a typical bowl shape with several small holes, they are almost cupped shaped with a single central hole. The cup shape allows the shisha to rest in it's own juices, allowing for a longer smoke and more flavor. Another benefit from Phunnels are they help prevent the juice from dripping down inside the stem. Most phunnels are slightly taller than standard clay bowls. Tangier makes Phunnels out of white clay/ porcelain in 3 sizes, glazed in various colors. Small (20-25g), Medium (40-50g) and Large (65-75g). MNHookah makes 2 piece glass phunnels in 2 (Small & Large) different sizes, in various colors. Other than shape, they are very similar to other glass bowls.
Scalli Mod: A clear glass insert used with both Tangier and MNH Phunnels. It fits over the center hole, with shisha packed around it. It serves several purposes: 1) prevent the foil from being dragged on the hole, 2) cuts back on the amount of shisha needed, 3) draws air thru shisha, then down hole to increase the flavor. MNHookah sells them (I believe Tangier's may as well).
Now that I've explained an bit about various types of bowls, allow me to make what few observations I have figured out:
- Smiley's (Pyrex too) heat faster. Use cheaper shisha until you have learned how to manage the heat.
- Glass screens can and will burn the shisha. You can put a few drops of water in the shisha to cool it down. Certain types of shisha do better with glass (drier types).
- Tangier's (MNH dependant on size) will hold ALOT of shisha. I highly suggest investing in a Scalli Mod.
- Tangier's does better with wet shisha (drippy juicy types).
- LEARN HEAT MANAGEMENT before investing in fancy bowls and pricey shisha. You'll saved your self a good bit of money and frustration in the long run.
- If your shisha is burning to the underside of the foil, reduce the amount you put in the bowl.
- Always WASH your bowls. Try to scrub off the blackened stuff, it can alter the flavor after time.
- Remember - ANY BOWL CAN BREAK. Take care, don't drop them, and NEVER force them down on the stem. It may not break in your hand, but shatter while using (skattering hot coals and shisha everywhere). Keep a couple back-up bowls.
And remember, experiment - What works for me may not work for you. Take this knowledge and run with it, don't use it as a bible but rather a building block.
(Ok, zen stuff over now - go smoke people).