Let's talk about green water.

ergo sum

AC Members
Mar 15, 2005
576
0
0
Doing a bit of reading this morning.

Seems the cures for Green water range from blackouts of about 5 days, daphnia in a fishless tank, daphnia cages in a fish tank, increasing N and or K to make P the limiting factor in a planted tank, diatom filters to polish the water, chemicals, flocculents in conjunction with diatom filters (or filter floss), to UV sterilization. Water sprite is mentioned as a good plant cure.

Causes seem to range from sunlight, new tank syndrome, chemicals for disease treatments, a reduction in plant health, growth, or mass, (pruning), messy fish tanks in general, especially those with higher light, and finally (at the end here Tom Barr claims) NH4.
http://www.thekrib.com/Plants/Algae/green-water.html

But what is it? What is really going on?

Let's talk about the 40 genera of euglenoids, dinoflagellates, and planktonic single-celled green algae. Seems some of these things are always hanging around, but most of the time they get eaten by the other mircofauna in the tank. (microscopic ciliates, rotifers and crustacea, especially copepods,)

http://www.skepticalaquarist.com/docs/algae/green.shtml

Welp a few things seem to jump out of all this to me. One is that Green water is a good thing in the sense that it is actually fixing, or helping to fix a problem. The other is that taken as a whole the real problem seems to be a lack of beneficial micro fauna. Seems like you can cure the problem by massively reducing the green algae (black outs filters etc.) but that will only work if you fix the underlying problem in the first place.

More of Tom Barr.
http://fins.actwin.com/aquatic-plants/month.200308/msg00269.html

Now we need to understand where the NH4 comes from in the first place. What that has to do with PH and we need to talk a little about bacterial filters.

Anyone care to comment or help?
 
Just that my green water seems to have taken care of itself in my tank....I just turned the lights off, didn't cover the tank, and did regular maintenance as usual....for about a month..

Course, the test will be.....now that the water is nice and clear...will it stay that way now that I am leaving the lights on for 12 hours a day.......

We shall see ! :D

oO(now, if only that smiley face were any other color but GREEN !!! :rolleyes: )
 
Last edited:
awsome!! This should be a sticky somewhere. It was the perfect amount of info convering everything I'd want to know about it. Great links. Thank you soo much!
( Love the drunken journal entry in the first link!) I think I am going to try the black out once my already stressed plants get a little stronger.

Lisa
 
When I decided to go planted, the first thing I grew with success was a lovely case of green water ;). The thing that seemed to work was patience, combined with good plant growth - at first I had the diatom filter on the tank almost daily, but as fast as I removed the problem, it came back. Once things were balanced out, it just vanished, nearly overnight.
Recently I let my maintenance and fertilization slide, allowed the CO2 to go a few extra days before I replaced the mix, and BAM!, green water again. It's a mild outbreak, and now that things are back on track I hope the slight cloudiness will clear on its own without a blackout.
I've never really thought about exactly why it appears or disappears, it's good that you brought it up so we can learn the reasons for both and figure out how to avoid outbreaks :D
 
Last edited:
The two things I'd add for quick reference are
#1. do not light your tank during fishless cycling. Light and ammonia will make algea no two ways about it.
#2. always remember that Green water won't hurt your fish, and is in reality not entirely unhealthy. it just looks bad. So don't panic, take your time and kill it with some information at hand. I have had fish live healthy for as much as 3 months in ea soup. not becuase I wanted to but because I didn't know how to eliminate it and didn't trust the folks I had to talk to at the time. MY fish were no worse for the wear than when they started.


I would also Comment that my experience with green water tends to support most if not all of What Tom Barr has to say on the subject (imagine that)

The new tank issue lends to the ammonia as wel as the organism level argument. Green water seldom (if ever) shows up in estabilished balanced tanks. I'll emphasize balanced in the sense of stocking levels, maintenance and light. Years ago someone sold me a really nice bright bulb for one of my Oscar tanks. this tank had an abundance of ammonia production due to the large fish in the small water quantity. it also had lots of phosphates because I was playing the buffer game back then. Nitrate levels were low, maintenance was good, but the actual waste production in the tank was huge. I learned a lot about green water in a very short time after buying my new bright bulb. the tank was healthy, as mentioned, but there were some serious nutrient imbalances that fed green water very well.
Dave

In my current plant tanks, I have only had green water around the end of my fishless cycle which I did some pretty dumb things (Light and plants during fishless) to create the green water in the first place. Once it was cured (blackout) it hasn't returned.


The
 
I think my green water came up because I had done a major gravel vac and stirred everything up down there...along with adding a different bulb to the duel strip light I have on the tank.

The tank was cycled....not overly stocked..(two dwarf gourami, 2 german blue rams and 3 otocinclus) and I hadn't made any changes in anything before the issue cropped up. I just turned the lights off and let it take care of itself...seems to be fine now and I have begun leaving the light on again...so far so good...
 
AquariaCentral.com