Dusty water?

In the past week-week and a half, I've come to notice that my axolotl's water is cloudy. At first, I thought this was just general uncleanliness, or caused by some food that I may have missed during clean-up, but after extensive cleaning with a siphon (I have sand as substrate), stirring up the sand, removing objects before siphoning, and doing 25-30% water changes and having no effect on the cloudiness, I've come to suspect that the problem is dust.

A bit ago, I had posted a thread about a film on the surface of my water, which turned out to be a layer of dust, caused by a fan that I use to keep the water from getting too warm. I got rid of the problem of dust on the surface (although there's still a bit of it in "whirlpools" by the edge of my filter), but I've come to wonder if perhaps there is dust building up in the water itself. What has me baffled is why the filter won't pull any of it out. Or, perhaps, is it something to do with the sand? I like how the sand looks, but if it's causing problems, I have no issue with taking it out.

I'd rate the "cloudiness" as a bit of a minor fog: I can see through the entire tank just fine, but like low-lying fog, the more distant objects seem to be paler and a bit hazy. Other details: There seems to be "white scale" (or perhaps, more dust) around where the waterline has been.

My tank is relatively small, since I have a 2 month old axolotl (it will be upgraded when Ailin gets bigger). The tank is about 2-2.5 gallons and 14.5 inches long, and with the fan, there is a high evaporation rate. Some dust and sand seems to be sticking to the inside of the plastic below the water level. Even with water changes, the cloudiness doesn't seem to change for better or worse. Unfortunately, I can't provide water parameters at the moment, as my pet store doesn't carry a water test kit that tests anything other than pH. My axolotl doesn't seem to be stressed, however, this is also my first axolotl so it is possible I'm missing stress signs, and I don't want conditions to get to the point where Ailin is stressed.

Also, the water has no foul smell or odor at all.

Any ideas as to what may be causing this or how to fix it?

Theres a few problems that could be associated with cloudy water. Bacteria blooms are common signs of cycling, so you probably wanna test your water. Do you have a light on your tank? Sometimes algae blooms aren't super green at first, and it just looks hazy. What kind of filter do you use? When I first setup my ten gallon tank it was already cycled, and I just switched the filter with a sponge filter, and it did not have sufficient mechanical filtration to keep the water clear. I had murky water even though the parameters were fine. Are you sure that tank is only 2.5 gallons? Depending on how big your axolotl it just might not be able to handle the bio load. If it's a larvae and really tiny it's probably fine, but if it's got it's legs and is a decent size it might be time to upgrade. But i mean my ten gallon tank is 20" long so you probably mean a 5 gallon.

Maybe it is an algae bloom. I do have a light, although it's not overly bright and the tank isn't too close to a window. It could be bacteria too, as the tank is a recent setup. There's another pet store about 20-30 minutes away, so hopefully they'll have a test kit and I can make a run there to get one. I have a Marina i25 internal filter, and it's supposed to work for up to 25 gallons. It doesn't say what type of filter it is, but I think the cartridge has carbon in it. I'm not fully sure on the exact gallon capacity of the tank, as it is actually a large Kritter Keeper (like the one here, with the dimensions of the large one at the very bottom) that was marketed mainly for terrestrial use, although it did say it could be used for an aquarium setup. Judging from when I've put water in, it's between 2 and 3 gallons at the most. My axolotl's about 2-2.5 inches long, so while the tank fits him sizewise, you may be right about it not being able to handle the bio load.

Thanks for your input!

You've got a mighty big filter for such a small tank. I would be worried about causing a lot of stress in a tank that size. When are you planning on upgrading to a larger tank?

As for the cloudiness, it's really hard to keep a tank that size stable. You'll have a hard time legitimately cycling it, and for no reason, since the axolotl will need a bigger tank in less than a few months time.

I was planning on upgrading once he got larger size-wise, but I may look into doing that sooner since the tank size could be causing these problems. And especially since you are right - chances are, he will outgrow the tank in a few months anyway. I'll look into making a pet store run tonight, to test parameters (I think they do it for free there) and look into a test kit, see what they have tank-wise, and see about exchanging the filter (this is actually the second one I have, as the first (which was for up to 10 gallons) ended up being a brand that even the larger pet store didn't carry replacement cartridges for.)

Anything else I should look into while I'm there? I can guarantee they won't know anything about axolotls, but they'll hopefully at least have the supplies I need. If I can get a larger tank tonight, do you recommend I stick with sand as a substrate, or should I go with bare-bottomed? Also, if bacteria are causing the cloudiness, do you know if it's possible to tell if they're the harmful type, and if so, how to deal with them?

Thank you for your help.

I'd try to get something bigger than a ten gallon. Your going to have to upgrade your fish tank eventually anyways, so might as well get the tank your going to end up with. I'd start checking craigslist, you can find some pretty sweet deals there. I wouldn't put a full grown axolotl in anything less than a 30 gallon, but they can survive in smaller tanks. Sand or bare bottom works just fine, whichever you'd prefer. I don't think that the bacteria bloom would cause any harm, but I've heard it's good to run an airstone if it's really bad just to increase oxygen in the tank.