If you think you.ve seen bad BGA, take a look at this;
The narrow, crinkly leaves look more like A. longiplumulosus than A. ulvaceous, and the flower colour matches, but both of those species normally...
Only if the heated water can flow along to the thermostat end of the heaterstat.
If the water flow around the heater is restricted it will probably crack the glass. The heated water can't move away, and the thermostat does not...
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