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From:
BWMy marine tank water has got a definite yellow colour, the water quality tests ok but it looks unsightly. Also my yellow tang is suffering from red blotches. I'm not sure if these are connected with the yellowness of the water. Has anyone any suggestions or advice?
From: HL
Use some activated carbon in a filter or portion of the sump where water flow will be
through the carbon. It should clear it up in a few hours. Discard the carbon after about two days, to prevent adsorbed substances from leaching back into the water.Just keep in mind that if you have MH's (or any very strong lighting), the corals, etc. could have become acclimatised to the lower light passing through the yellow water. If the water is cleared rapidly, the much brighter light now reaching the inverts could affect them negatively in the short term (even possible bleaching), so reduce the photo period for the first 2-3 days after filtration, if this is a problem.
From:
CGI am having some trouble with my salt-water tank -- a yellow tinge to the water, which seems to be related to my recent change in water supply. I was previously purchasing my salt water "pre-mixed" with RO water from an aquarium store. Lately, I have been using my own well water and mixing the salt myself. Although my salinity and pH, etc. are up to standards, the
water is now a yellowish colour. Tried using some carbon in my wet/dry system, as well as more frequent water exchanges. But the yellow colour is persistent. Any suggetions?
Oh yeah, one more thing. I have no idea why this happened to me, but I was having a rather high level of phosphates in the tank (1.0-ppm) and when the lights were out, I noticed that my tank had a yellowish cast to it when I looked down the long way. Didn't really notice when the lights were on. I put a phosphate sponge in there, which immediately reduced the level of phosphates, and the yellowish tint disappeared. Don't know if the two were related, but you may want to test your water for PO4. Does the water you put in the tank have a tint to it before you add it (i.e. in a white pitcher) or only after you add the water to the tank?
From:
CGYou may have something there... I know there is no yellow color to the water when it is in a white or clear container, but you made me remember that we have a bit of problem with rust
build up in the shower, toilets etc. Seems I have a high iron content. Problem is I don't know how to eliminate the iron prior to the water exchange. Still researching!
From: BC
I'm sure your LFS should have something for iron removal. This has not been a concern of mine since I live in the city limits and iron is filtered out for us. If they don't, another solution (however not cheap) is to invest in a water softener/purifier. I would also check into buying RO water either from your LFS or local grocery store. I've lived in the country before and used well water. I've never come across any well water that did not have a large iron content. Some areas are higher than others, but if you are having a rust problem, as you said you are, then the iron content must be up there pretty high.
From: HL
How old is your tank, and what type of lights are you using? Lights do tend to lose their colour spectrum with age, and usually turn more yellow. If the lights are more than ~ 1 year old, you might want to look at this possibility as well.