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green water problem...

1557 Views 15 Replies 6 Participants Last post by  lartist
Hi everyone!

I start a new 65 gal tank 2 months ago and since than I have a problem the green water. Last week, I taped cardbord on the tank to totally obscur it. 3 days later, after removing the cardbord, the green was gone but the water still was a bit cloudy and white. But 1 day after put on the light on, the green water came back. I put rowphos in my filter to reduce the phosphate but water is still the same. Now, I plan to do a treatment with a massive dose of excel. In a another tank, I had very good results with black algea.

Can someone help me on this one!

Au plaisir

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I had an outbreak after uprooting a huge mass of plants and what worked for me was a diatom filter, or more exactly a HOT Magnum with the micron cartridge and DE. I ran it for a couple of ours per day over a couple of days and the greenwater was and is gone.

I'm not sure Excel will directly affect it. It will however help your plants if your CO2 is lacking a bit. You'll still need to address the cause of the greenwater. Make sure your CO2 and ferts are optimal for the amount of light you're using and keep in mind the more light you have the finer line you walk between algae and no algae.
Thank for the info Jeff...

I do not have a lot of light... maybe 1.5-1.7 watts per gallon and the pressurised Co2 system profite 3bubbles per second. I'm wondering if the spectrum of the T5 bulbs can provoque this situation?
I don't know. You read some posts that say particular spectrums contribute to algae growth and then others that say it doesn't and each argument makes sense to me. I'm so easily swayed, lol.
I follow your advice Jeff... Just installed polishing pads in my filter (Fluval 305). Will see what will happen...:)
I had the excact same problem and did exacly as you but after I turned the lights back on I installed a UV filter. My tank is unbelievably clear!
IIRC GW outbreaks come when ammonia levels are high. If I had to guess I'd say your tank is not cycled or maybe you've added a heavy bioload lately?
This tank is running since late june. I had fishes gradually into the tank maybe one month ago but, at that time, the water was already green. For the ammonia level, I cannot tell you the level because I don't have a test kit to test it. The nivel of nitrite an phosphate are almost at 0. Can a tank need that much time to get cycled?

Don't kill yourself trying to solve the problem with GW. Just install a UV and enjoy your tank. I have many tanks and just one kept getting GW. I installed the GW ran it 24/7 and the tank did great. Also if the flow isn't too much the UV will kill parasites that might attack your fish, so it's a win-win. Once you get the UV and the water clears, you can always shut it off and see if the tank remains clear. There are many professional aquarists/scapers that run UVs 24/7. It also helps acclimate new fish, by killing pathogens in the water that attack fish when their stress levels are up.
Yep, either a UV or a diatom filter will help eradicate the GW in just a few days.
Can you tell me more about those diatom filters? Brand names? models? I don't know a lot about this kind of equipment...:noidea:
You can get the Vortex line of filters which include Vortex XL, Vortex Freedom.

I use the cheaper Magnum 350 filter w/ micron cartridge. I just load diatom powder in and it's good to go. :)
A HOT Magnum with micron cartridge and diatom powder works well also.
I will do a little research on those...

I've put some polishing pads in my fluval and the water is better but not totaly clear. I think that will wait a bit to see if it is a question of cycling. Can take more than 2 months to cycle a tank? If there is no change in a few weeks, I will look for an UV system...
Get a clean, white cup. Scoop up some aquarium water and look inside. Is it "clear", or is there a slight green tinge?

If it's green, you have GW.

It takes my tanks around 3 weeks to cycle usually. Yours should've cycled in less than 2 months.
It's definitely green water... I do water change with a white bucket and you easily see the greenish color. It is sad because all the plants in the tank grow well, are beautiful and there is not a single algae in sight.:( I would like to find the problem that provoque GW without installing costly equipment...
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