allsps40
New member
No, it's not normal. If you have brown residue in your pumps and buckets, you either have algae or bacteria growing on them. The water should still be crystal clear (assuming you mix the water correctly and your bucket is clean to begin with). I have never seen any brown residue from IO. Even RC is not always brown (just occasionally).
I dont store water in my mixing buckets I mix it and use it. Over time my pump and bucket get a brown scale build up. It is ca and mag that did not dissolve this is very common and normal. I have noticed faster build up with reef salts. There are posts about this scale build up. I agree the water should be nice and clear and it is except for those few buckets of RC and IO I got a while back.