My tap water is treated with chloramine.

I'm told that the let-it-sit method of chlorine removal doesn't work with chloramine, so I'd like to buy a small catalytic carbon filter for my aquaponics step.

Does anyone have a suggestion for a relatively inexpensive, but also good filter? I'm hoping to find a model for which the refill cartridges are easy to get... and likely to stay that way for a while.

Thanks,

B