According to what I've read when considering a guppy tank, they can survive in water 68-79* F, but thrive at water of 74-78* F. I don't know how hardy guppies are, but IMO, don't chance it. Spend a few bucks for a new heater.
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150g long S Amer cichlid; 90g C Amer cichlid; 90g Malawi cichlid; 40g Tanganyika cichlid; 29g "Shellie" cichlid; 29g Pea Puffer. 6,500g koi/native catfish pond; several smaller ponds
According to what I've read when considering a guppy tank, they can survive in water 68-79* F, but thrive at water of 74-78* F. I don't know how hardy guppies are, but IMO, don't chance it. Spend a few bucks for a new heater.
My parents ended up surprising me with a new heater for the tank so now it's all good.