Pink Water

[divemaster99]

One of my 30 gallon tanks has been setup for about two years now, and about 6 months ago, the water in the tank started to develop a pinkish-stain about 12 hours after doing a water change. The water doesn’t get cloudy, just tinted, and none of the fish have ever shown symptoms of distress when the water is pink. This color always fades on its own within a week or so of showing up. I’ve been sticking to a regular schedule of 50% WCs every 2-3 weeks for this tank since I set it up, but as I said, this pink water situation only arose about half a year ago. None of my other 5 tanks ever get this pink stain after WCs (or at all). I have the same substrate in this tank as I do in several others. Two oversized sponges for filtration (same as several other tanks). Regular old rocks, driftwood, plastic plants, PVC, and a pleco cave for decor.

Any ideas? I’ve read about several other people with this exact problem and no one ever seems to know what causes it. Either way, it’s not harming my fish, so I’m not too worried, just curious.

 

[divemaster99]

Water parameters are all fine, by the way. Ammonia and nitrites at 0 ppm and nitrates always under 40 ppm. pH sits around 7.4-7.6. Water temp is 78°F.

 

[Deadliestviper7]

Food build up in filters or substrate?

 

[kno4te]

Any new decor or gravel? Been feeding bloodworms?

 

[Kittiee Katt]

Any new decor or gravel?

I was going to ask this also.

One of my mates had a chunk of rose quartz (I think, it may have been something else) sitting in a container on his porch and when the rain filled the container his pretty pink stone turned clear and the water was pink.

 

[esoxlucius]

When I eat beetroot my whizz turns bright pink! This won't help your problem but I thought i'd just share it with you guys.

I doubt it'll be your substrate as you've got the same in other tanks, with no problems. What i'd do is take out all decor during your next water change so you've just substrate in there. Fill your tank back up and observe. If you've still got the pink tint then at least you've eliminated the decor side. If you haven't got the pink tint anymore then add your decor items one at a time over a couple of hours and observe.

Just a side note, is your gravel actually all the same? You don't have any rogue stones of different material in this tank do you? Just asking because kittiee katt makes a good point.

 

[Drstrangelove]

I would probably remove all the decor (and if needed the substrate) and see if that eliminates the color on the next WC. An alternative is to simply place the decor (and a sample of the substrate) directly into a container, then add the same type of water and chemicals to that container (as you do during a WC) to see if you get the same color.

It sounds like something in the tank is reacting to something that happens during a water change (e.g., new water, salt, dechlorinator, ferts, higher pH) and the reaction releases a cloud of tiny (sub 40 micron sized particles) that are pinkish colored. Over time, the colored particles are filtered out or trapped in the substrate. The best bet is to test items using the same conditions until the color is replicated.

It's certainly not a common issue, so an object leaching color is my guess.

 

[kno4te]

When I eat beetroot my whizz turns bright pink! This won't help your problem but I thought i'd just share it with you guys.

Thanks for sharing lol.

 

[divemaster99]

Thanks for the suggestions, everyone.

I haven’t put any new decor in since setting the tank up. The substrate is pool filter sand (I washed it thoroughly before putting it in the tank 2 years ago). I do, however, stir up the substrate every time I do a WC so that I can vacuum any trapped feces or food. I wonder if that’s where that color comes from... But, I stir up the same substrate in every other tank for every WC, so I doubt it.

kno4te, I feed all of my tanks bloodworms on a daily basis, but this is the only one that gets the pink color.

Maybe I’ll try removing decor next. I’m just confused as to why it goes away several days after a water change if it is in fact leeching from something in the tank. I’d think it would get more potent over time if that was the case.

 

[skjl47]

Hello; A vague notion has occurred to me but I cannot think it out just now. A nagging thought having something to do with litmus paper or titration. may be nothing but I posted so I can find this thread if my thinking clears up.