The output seems a little low but not ridiculously so. I think Solar panels are rated at an output of about 16V, so the very best an 85W panel will give is about 5A - and that would be with the panel angled directly towards the sun at midday. Mount the panel flat and you could halve that even in the Canaries
If possible try connecting each panel in turn individually through the controller and see what output (in Amps) that gives. You should also record and tell us what voltage you were seeing at the battery when you were getting 3A current.