i dont think it would damage the battery, the current from the pump isnt that high, what pump are you using? or are you using two pumps?
i dont think it would kill the battery, if theyre new then chances are there is nothing wrong with the battery, so it would be the charger, firstly cheque the charger, if there are display lights are they on and some have inbuilt fuses, you may have accidentally touched the + and - together and blown the fuse, these are normally 10 amp, see if there is a fuse there underneath or at the bottom you can pull them out?


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replace it and dont touch the wires together and it should work, or
i dont suppose youd want to but if you are really desperate i live in lakenheath about 30 mins away and can have a fully charged car battery ready for you, to pick up early in the morning- or you could pick up the battery tonight and two of my chargers for 12v batteries which work! put them both on overnight and you should be ok, but its upto you. i dont know how long it would run your system for but fully charged, i think its about 48 ah,. i would probably need it back though... as its from one of my cars!