Thermostats. Dimmer Vs Pulse

Question
Hi Pam,

Hopefully just a quick one, what is the difference between running a Pulse thermostat Vs a Dimmer thermostat?

We have 2 tanks, one small (65ltrs approx) and one large (150ltrs approx) we have the same type of thermostat running in both. The large viv has a cermanic bulb, the small viv a heat bulb. Both are at about 70 at cool end, 90 at hot end and 100 in basking area. The guy in the local pet shop said i should be running different types of theromstats for the different bulbs..both tanks run well and at the correct temperatures, only difference i can see is that the light on the thermostat stays on in large tank and turns on off as required in small tank. Do i need to be concerned?

Answer
 There is no difference is thermostats if you are using incandescents for light and heat.  However, mercury vapors should never be on a dimmer, ever.  
  If the smaller one's light shuts off, and the animal has not had the correct amount of UVB / basking time (8 hours) then I would suggest a lower wattage bulb.