Suddenly cloudy water?

[zim64half]

Howdy all.

Here is the story.

72 gallon tank with 6 discus and one pleco.
The discus are all 4-5" in size, the pleco maybe 6" long.
Gravel bottom, with 2 large pieces of driftwood as decoration.
Eheim cannister filtration system.

Fluorescent lights - twin 32 watt bulbs that came with tank.
Lights are on a timer. Right now - on about 6 hrs a day.

Big heater - tank is a steady 84F.

Water tests reveal little - only that the water is very "soft".

PH, Nitrites, Nitrates, and Alkalinity are all "good".

Tank has been established now for over 12 months with few problems.

Suddenly, about a month ago, over a few days, the water became
very cloudy.

I did another water test, and all of the categories were still in the same
ranges as before.

I know - First answer is that I need to change the water. I have been doing regular changes (20 gal every 2 weeks)

The cloudiness has a yellowish green tinge to it.

My first thought is algae. But with the pleco in there, there is very
little algae on any of the surfaces in the tank.

Any thoughts on what I should be doing different?

Thanks,

-Jason Z.

[FishLover]

20 gal every 2 weeks is not nearly enough.

You need to change about that much water in every two or three days.

We need numbers when it comes to water parms

[zim64half]

Okay - numbers...

Nitrate (NO3+): 30ppm
Nitrite (N02-): 0ppm
Total Hardness (GH): 0ppm <--- (lowest reading on scale)
Total Alkilinity (KH): 120 ppm
pH: 6.8

[Merrilyn]

Okay - numbers...

Nitrate (NO3+): 30ppm

Welcome to the forum Zim.

There's your problem, right there.
Your high nitrate reading is supplying food for the free floating algae. You need to increase your water changes to around 50% of the capacityof your tank a week. Now you can do that in several smaller changes during the week, (which is best) or one large water change a week.

Whilst your pleco will do a great job of keeping surface algae under control, he can't do anything about free floating algae in the water. If you want to keep that under control, then you need the larger water changes or you can add a UV unit to your tank. That will keep your water crystal clear and remove any pathogens or bacteria floating in your water.

Try to aim for a nitrate reading of less than 10 ppm.

Your bio filter removes ammonia and nitrite, but water changes control your nitrate levels.

[FishLover]

BTW, 30ppm nitrate is way too high for discus. It maybe ok for other fish, not for discus. High nitrate also indicating the water is not in good condition due to lack of WCs.

Not only WCs will keep your algae in control, it also keep other nasty things in check. Bacteria boom quickly in old water, so are other things that could harm your fish. By keeping up the WCs, you also keep these nasty things in check too.

There are two major possible reasons for cloudy water: Algae boom or bacteria boom. Both attribute to poor water condition. WCs can help in both case.

[zim64half]

Can someone elaborate on the UV unit?

What is it, where does it usually go on the tank, how much do they
cost, etc...

I try to keep up with the water changes, but it is somewhat of a pain for me.

I have very bad tap water and an inline water softener system - the pH is
up around 8.

I buy bottled "Hinckley & Schmidt" water in 5 gal bottles too. It reads
low - like 6.2 pH.

When I mix them together 50-50, I get a good 6.8 or so.

So every time I change out 20 gallons of water, it costs me 2 bottles - or
about $11.00

Definately a bummer. I will see what I can do I guess!

-Jason Z.

[FishLover]

You better off use other methods.

If you are not looking to breed them, I would go with Discus Buffer. Much cheaper. My water tap is 8.2 and I can adjust it to 6.3 without any problem.