So i had a little algae growing on my dw and the glass needed a good clean and i wanted a nice clean tank for the new tenant ( a gbr) cos apparently they require a super clean tank, it wasnt dirty, i just decided to do a full noise clean, deep gravel vac, plant, ornament, glass and filter clean and reset the layout with some additional caves and overhangs. I thought the number of ramshorns was at about 7 cos that is how many are on the glass every morning but no, they were everywhere, on the glass, the ornaments, the plants and even in the filter so i employed the old "push" method of control, which my harlequins thoroughly enjoyed, lets just say i did the killing, they hid the evidence, at last count i was up to about 25.