Cloudy water and dropping pH

[liuj1]

Well, after some time of calm and no problems, My 25 g tank is experiencing cloudiness, and, I recently discovered, severely low pH... we're talking in the 5 range, according to the Tetra pH test.

The cloudiness is new, as I have not made any new additions to the tank, nor have I been overfeeding the fish. Nitrites and Ammonia are zero, and Nitrates are low (third from the left on the test kit, once again, I don't remember a number). The tank contains about 20 cardinal tetras, 5 sparkling gourami and 2 green sunset platies.

I conduct a 4 gallon change every week, with one monthly 6 gallon change in place of the 4th 4 gallon change, each time vacuuming the gravel. My tank stats are in the sig, but can y'all think of any particular reason my pH has dropped so rapidly?

I have been doing 2 gallon changes on a daily basis now in an attempt to raise the pH slowly, but that is having little to no effect. Any advice as to what might be causing the cloudiness would be appreciated. Other recent activities include changing the filter bag and charcoal, but this happened after the cloudiness occured.

[OrionGirl]

What's the pH and KH of your source water?

[liuj1]

Oops, those would be good things to have, now wouldn't they?

The pH of the water is 7.0 approximately. As for the water's buffering capacity, Alkalinity = 80.

More updates-- Nitrate is about 30 ppm.

When I returned home today, the haziness was ridiculously thick, and I hcanged 6 gallons, which didn't really do anything. The fish don't seem stressed-- at least, they're not showing outward signs of it.

[ScottoMacD]

Have you done a good cleaning of the gravel? I know that you vaccum but how complete is it? Does a lot of waste come up when it is vaccumed?

Excess organic waste in the gravel can cause cloudiness and will certainly cause a ph crash once it builds up enough.

The cloudiness can also be caused by a bacteria bloom. I get allot of customers getting a hazy look when they change the cartridges on their whispers. Bascially when the cartridge is removed you take a fair amount of the bacteria with it. Unlike some of the other filters on the market they have no bio-wheel (penguin, emperor) or sponges (aquaclear)

If it is this that is causing the problem what you can do is everytime you change the cartridge tear a piece of the floss off of the old cartridge (about the size odf a silver dollar) and jam it behind the new cartridge. There should be enough bacteria in that piece to help seed the new cartridge faster and hence should avoid the bacertia bloom.

[liuj1]

Scott, thank you for your input. The cloudiness occured before I changed the cartridge, and based on what you're saying, the fact that it's getting worse is not a surprise. Vacuuming brings up a decent amount of waste, but I have done constant vacuuming, at least 1x a week. That said, I'll continue cleaning, water changes, and let my filter continue to build. If anyone else has any input, it would be much appreciated!