No they do not.
For Hot Tubs to remove debris from the bottom of the spa it requires a suction point on the floor of the Hot Tub.

Our Hot Tubs skim water from the top surface to give two major benefits:

• Any floating debris is immediately drawn into the filters and trapped before it enters the pumps and pipework rather than going into inaccessible pipework under the hot tub where it may become trapped and cause a blockage. 
• Bacteria will thrive in the hottest part of the water at the top. Skimming the water from the top means that any bacteria is immediately drawn through the filters where, if not trapped, it is introduced into the bacteria killing zone of the Ozone injector or ACE system.

How should I remove heavier debris?

Heavier debris such as sand can be easily removed using our hot tub vacuum accessory online, or in your local hot tub showroom.