Marina (Hagen) 300 watt Submersible Heater

[MNG]

I have this heater, rated for up to 80 gallons, in a 65 gallon tank.

The temperature in the tank was about 74.5 degrees F. Over a day ago I set the thermostat on the heater for about 83 degrees, in preparation for some fish I plan to acquire that prefer warmer waters.

After over a day, the water is still only about 77.8 degrees, although it is getting gradually warmer. 

Is that the expected performance for such a heater? Is this a safety feature of some sort? Will it ever reach the set temperature? How should I set the thermostat to ensure the water is 80 +/- degrees? 

[KBOzzie59]

Open top?

Room temperature?

On 7/21/2021 at 10:55 AM, MNG said:

Is this a safety feature of some sort?

Doubt it.

 

On 7/21/2021 at 10:55 AM, MNG said:

Will it ever reach the set temperature?

Possibly.

 

On 7/21/2021 at 10:55 AM, MNG said:

How should I set the thermostat to ensure the water is 80 +/- degrees?

You should set the thermostat for 80+.

[MNG]

On 7/21/2021 at 2:53 PM, KBOzzie59 said:

Open top?

Room temperature?

Doubt it.

 

Possibly.

 

You should set the thermostat for 80+.

Closed top, room temp is about 68 or 70 F. AFAIK, that should not impact things - the heater is completely submerged and thermostat should adjust the water temperature, regardless.

Tnx

[KBOzzie59]

Room temp will have an impact, to a lesser degree since it has a top.  Is it fully submerged?  Depending on when it was made it may actually no be fully submergible. 

 

[KBOzzie59]

This is a 20 long with an Aqueon 50 watt pre-set heater (78).  Has a top.  Room temp is blue, water temp is green.  Temps swings 5 degrees.

 

[MNG]

On 7/21/2021 at 10:15 PM, KBOzzie59 said:

 Room temp will have an impact, to a lesser degree since it has a top.  Is it fully submerged?  Depending on when it was made it may actually no be fully submergible. 

 

It is fully submerged. Set it to max - 89 degrees F, over a day ago - water won't get past 79.5.  Maybe there is something wrong with my thermometer? It is digital - I'm going to get an old school style thermometer.

[MNG]

On 7/21/2021 at 10:22 PM, KBOzzie59 said:

This is a 20 long with an Aqueon 50 watt pre-set heater (78).  Has a top.  Room temp is blue, water temp is green.  Temps swings 5 degrees.

 

Mine doesn't vary that much based on the thermometer I have, but I have the heater set for 89 (the max) and after a day the temperature in the water won't get past 79.5. I'd like it to be 82 +/i  for Rams or Discus.