right everything seems to be ok the LLL that showing on the display looks like the heat is A LOW icon indicator. what i did found out is that while the heater was in the bucket of water and the temp probe was towards the bottom of the bucket the set temp was on 25c it did stay around the 24.6-7 c in which was ok but if i moved the temp probe up towards the middle of the bucket. the heating turn on and rise up to 25.1c and then the cooling switched indicator turn on and then i moved the probe again towards the top of the bucket and then the heat indicator turn on again rise a few degrees and turn off . so it looks like i panic a bit with the LLL .what am thinking is if the heater heated the bucket of water to the set temp ie @ 25c all the water in that bucket should be around the 25c mark by moving the probe around from the bottom of the bucket to the middle and then the top gave me slightly different temp readings. so its going to be important where you going place that temp probe in your fish tank.where would it be the best place to put it? in the main display tank ? towards the bottom,middle,top or in the sump again towards the bottom,middle,top, away from the main heater in a different chamber?.by the way i did not rigged up any cooling fans to the unit for testing but clearly shows on the display the cooling would kick in ok.
the unit is by simplyaquaria an equivalent to elitech stc 1000