What's Happening To My Temp?

[Beemeeup]

Tank size: 175 litres
pH: 7.1
ammonia: 0.0
nitrite: 0.0
nitrate: 5.0
kH:
gH:
tank temp: 29.5

first day for fish in cycled tank (14 fish about 1 inch each - two dwarf gouramis - 2 rosy barb - 5 dwarf rainbow - 2 white cloud - 2 pakistani loach - 1 zebra danio)

heater set to 25 centigrade

alcohol thermometer showing 27 centigrade

digital thermometer showing 29.5 centigrade (replaced by lfs in case faulty - new digital still records 29.5)

room temp - 22.5 centigrade

room radiators off

2 * 30 watt lights with reflectors

turned heater off - temp remaining at 29.5 for last hour

before heater was turned off the digital temp was 29.8 - i turned heater down to 20 centigrade - still could see it turning off and on?

i can only think that the lights are creating the intense heat and / or the heater/thermostat which is an Elite 200w is faulty

anxious that the fish will not suffocate tonight - the digital thermom is set to warn me if the tank temp goes to low in night.

i dont understand why the temp in the water is so high when the heater temp is so low. also why there is a diff between the alcohol reading and the digital reading.

am trying to think of a way forward. one other point is the heater is on a trailing socket with the filter.

any advice or help please

 

[jonny-5]

i know you have stated your tank is cycled but how long as your heater been switched on? if it has been on since you started cycling the tank the temp should be steady temp as set by you,so i would say the heater is at fault!! Same for the lights aswell,depending what lighting it is i.e flourescent tubes run 50 times cooler than normal bulbs

 

[Beemeeup]

i know you have stated your tank is cycled but how long as your heater been switched on? if it has been on since you started cycling the tank the temp should be steady temp as set by you,so i would say the heater is at fault!! Same for the lights aswell,depending what lighting it is i.e flourescent tubes run 50 times cooler than normal bulbs

i did a 90% water change this morning so the water temp was diiferent to the temp during cycling - i tested temp after the water change and it was reading 27degrees centigrade on the alcohol thermo.

 

[WILDER]

Don't switch the heater off, my tank temp gone up as the temp gone up in the last couple of day because of the hurricane, as long as you increase areation in the tank they should be fine.

 

[Beemeeup]

Don't switch the heater off, my tank temp gone up as the temp gone up in the last couple of day because of the hurricane, as long as you increase areation in the tank they should be fine.

forgive a daft question but as i am a newbie - how do you increase aeration?

 

[WILDER]

Some filters you can turn the water flow up and down.
If not you will need a pump and airstone that creates bubbles and some fish love playing in the bubbles.