Most of us have some amount of tea color...decay of plants, muck, etc. I
suspect you will have to tolerate it or go to carbon...repeatedly.

Our water is very clear but tea colored. We have got used to it.

Water clear in a glass here. I'd go with 10%/weekly water changes and see
if it helps. I think you'd go thru too much carbon and that could get
pricey and you need to get use to doing those water changes once you get
koi anyway. So establish a routine. ;o) ~ jan


See my ponds and filter design:
www.jjspond.us

~Keep 'em Wet!~
Tri-Cities WA Zone 7a
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