Algae Bloom gone wild?

[g-man]

I have a 25 gal tank thats been up for 6-8 weeks now.. All levels are normal (PH, alkalinity, Nitrite, Nitrate) Fish, Crabs, snails are all doing fine..
10 days ago my water turned green over the weekend. Lights are on a timer for 8 hours a day; my water is more green than ever - you can't even see through the tank..
Do I turn the lights off for awhile?
I read that a water change may mess up my tank cycle.. I also read that my tank may die do to loss of oxygen if I am not careful!
Any advice??

 

[beaslbob]

The green water/algae bloom is caused by the combination of nitrAtes carbon dioxide and light. Could be also phosphates and ammonia but less likely. Those things all lead to plant growth and elminating any one would clear up the water. For instance if you turned your lights off the water would be clear in about a week. You would also have more nitrates and carbon dioxide.
The best thing is to use desirable plant life (macros, marine plants) to consume the carbon dioxide and nitrates. No only do they contraol algae but provide many other benificial effects.

 

[g-man]

I do have macro algae in the tank and added more 4-5 days ago. still seems to be getting worse..
Is it OK to kill the lights for a week?

 

[jedininja]

Hey G-man,
Tell us more about your system. What type of equipment are you runing? How much live rock? How many fish do you have in there? How often are you feeding? Are you using tap water?
If you do not have coral in your tank, I recommend cutting your lighting back a lot. One of the reasons why your readings may seem normal is that that the algae bloom has consumed most of the nitrates and phosphates in your system and that is why it doesnt show up in your test.

 

[beaslbob]

Originally posted by G-man
I do have macro algae in the tank and added more 4-5 days ago. still seems to be getting worse..
Is it OK to kill the lights for a week?
If the macros are growing then definately. If they are not doing well then setup another container to culture them in. But either way you will need macros in the system and reduced lighting to allow the uglies to die off and the desirable wot catch up.

 

[shine~on]

If you run some Carbon, that should help clear it up.

 

[fender]

You say that you have Fish, Crabs, and snails and that your tank has been up for 6-8 weeks. I would assume your cycle is done, especially since you're not seeing any nitrite readings.
What is in your tank (fixh etc.)? What are doing for filtration? What about water movement?
What did you start off with for water? Was it tap?
You may have some high phosphate or nitrate levels in your water.
I would suggest doing a 30% water change - try using SO/DI water.
Do a couple more water changes in the 30% range over the next week or two.
What is your lighting? 8 hours is not excessive and unless you are runnig some heavy duty lighting turning off the lights will only be a band aid.

 

[beaslbob]

I had one tank several years ago that had this problem. I used a canister filter with carbon and a water polisher cartridge. It cleared up in two days. the three days later it was all cloudy and green again. By using plant life and reduced lighting, the tank cleared up in a day and stayed clear.

 

[g-man]

beaslbob - The macros are doing good (even growing a bit) I do have a 5 gallon that I could move some macro into if needed..
jedininja - Tank breakdown -
25 gallon..
Running a Power Compact smartlamp - 65 W and recently added (2) Allglass brand aquarium - 11 W mini flouresctents to light up the tank a little more..
Prizm - protein skimmer
- I did have an amonia/carbon filter running in the prizm for about a week. Could that have stripped my tank of anything to cause the bloom? I ran the filter to clear up the water a bit, added the lights (10 hr timer) and over the weekend the tank went wacked!
Rotating Power head
Deep Sand bad (3"1/2 - 4") with some live sand purchased originally.
No Live rock (just base rock)
1 Percula clown
1 Yellow tail
1 Striped damsel
1 sally light foot
1 Emerald
2 hermits
1 Peppermint shrimp
1 Orange foot snail (moon snail?)
2 regular ol' snails
5-8 Nassarius snails
Macro algae
1 cluster of Xenia (It looks like waving hand xenia)
3-5 spaghetti worms
3-5 bristle worms
That's all I can think of in the tank..
Thanks for all your input and responses
G