hahaha bro nic...instead of having your filters below which is impossible on old old aquarium , u could of course place it by the sides if space permits. oh yes...those ceramic bio rings are truly expensive ...and to fill in all my filters , i would need at least , 50 kilos x 12 setup= 600kilo....waaaah, die la...i would have to go on goreng pisang and kopi-o for at least two years i use crushed coral instead, big size for drys and smaller ones for wets. for south american set ups i avoid using corals , but use my mum s hair roller for the drys and fine harden clay chips for wets. ok tips!...i use natural dried Peat Moss for lowering the ph. can be bought at the plants and flower nusery for less than rm5 per kilo. steal your sister or wife s stockings ..fill it up and place it your filter and you are in business...i like the light tannic stains...just like in the amazon. i hardly could afford the stuff they sell at the FS for lowering or getting your PH up, so i use this method for lowering the ph , and for higher ph i use ...soda bicarbonate....in another words ...baking powder...yup, the one mum uses to bake her cakes. for KH...ah , this is abit more complicated...i use a home made reactor. i dont want to go into this unless u pm me la