Aquarium Water Overheated - How To Recover

  1. G

    Gary1962 Valued Member Member

    Hello Everyone

    Need some advice on how to safely bring down the temperature in my aquarium.
    And any other advice on helping my fish recover without further loss.

    In recent weeks my thermometer was showing a drop of 1c on average from the usual 24-25c.
    Despite turning my two 100w heaters up to over 30c, there was only a small uplift in temperature.

    Foolishly, only just today realised it could be that my thermometer has become inaccurate.

    Bought a quality new thermometer - a JBL premium glass design. This confirms he temperature is actually 33c!

    Now, this is partly due to the high ambient room temperature, due to the warm weather. (despite switching the heaters off 2 hours ago, the temperature is still 30c).

    LFS have advised to set the new heater at 25c and let the temperature settle naturally.

    Current stocking is:
    Male Betta
    Rummy Nose Tetra X 6
    Harlequin Rasboras X 5 (lost 3 in last 2 wks)
    Cardinal Tetra X 6
    Sterbai Cory X 6
    Otocinclus X 2
    Amano Shrimp X 10

    87L high aquarium
    Ammonia & Nitrate - 0
    PH 8.2
    Nitrate 40-80

    Eheim evco pro 200 cannister filter
    Water changes - 33% weekly.

    Thanks
     
  2. 8

    83jase Valued Member Member

    Let it come down slowly unplug em
    Take lids off if there is any can use fan across top but don't want to drop temp too quickly!!

    use thermostat inline of your heaters to avoid it happening again
    Always have two quality temp gauges 2 important lessons I learnt with failed eheim jager heater no fatalities luckily
     
  3. OP
    OP
    G

    Gary1962 Valued Member Member

    Grateful for the shared lessons Outside temperature here is 25c currently. It's due to be thereabouts or higher for the next week.
    I guess I shouldn't try to manipulate the temperature via water changes? It'd only be a temporary effect anyway.
    Sorry if I'm being a bit slow.. but could you explain what you mean by 'thermostat inline of your heaters' please?
     
  4. BReefer97

    BReefer97 Well Known Member Member

    No, you don’t want to bring the temperature down through water changes. That would drop the temp too fast, you want the temp to drop 1-2 degrees every hour, any more than that and it could shock the fish. Good luck! Had a little bit of the same issue in my nano tank.
     
  5. 8

    83jase Valued Member Member

    Since your temp 33 I'd let them come down slowly avoid shock

    Thermostat inline controls the temp externally and cuts power to the heaters so basically preset your heat what you want or higher on the heaters thermostat and use the external thermostat to take control let's face it heaters are the biggest let down and unreliable .I'm really surprised I don't see many more talking about running external thermostat for there heaters eBay Amazon lfs sell them

    This is the unit I run its very accurate heaters plug into also a
    Has cooling function run fans etc good investment
     

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  6. mattgirl

    mattgirl Well Known Member Member

    Fans blowing across the tank will be the best way to get it down slowly. Top off the water as it evaporates with cooler water. Since you will just be adding a small amount due to evaporation it won't be enough to lower the temp too quickly. Just make sure the water you are topping off with is at the temp you want the tank to be once cooled off.

    Hopefully by doing it slowly your fish will be alright.
     
  7. OP
    OP
    G

    Gary1962 Valued Member Member

    Thanks 83jase now I see exactly what you mean.
    Mattgirl & Breefer97 thanks for the further detail.
    Really appreciate the great & swift replies today everyone!