Green Water Issues

Kathy · 04-26-2007, 02:23 PM

My tank water has been green for about 5-6 weeks now. Although it doesn't bother the fish, it is hard to see them.

I've read many things on it, high nitrates, high phosphates, too much light, overstocking, over feeding. I'm probably guilty of the last three.

Nitrates were 80ppm, but I've decreased feeding by about half gradually, and yesterday they were at 40. Phosphates I have no way to measure. I've also been keeping the light down to about half of time that I had it on, so maybe down to 8 hours. The past few days I've kept it off all the time.

I'm patient and the water seems to be clearing.

I've read about blocking all light with towels for 3-5 days? Does it help? My tank is in a shady corner, so no direct sunlight, not in a bright room either.

I've read don't change the water at all or change 15% at a time, depends where you read. I've done 2 water changes of about 20% in the past 5 weeks. Will more frequent water changes help the algae clear?

I'd reduce feeding even more, but I found a dead tiger barb partially eaten floating on top the water this morning.

My tank is 30 gal, stocked with

6 African cichlids (less than 4 inches each)
6 serpae tatras
7 scissortail rasboras
3 tigerbarbs
6 otos

I have 2 filters running, and a bubbler
no plants

I've read adding fast growing plants could help, I could add some echinodorus from my other tanks.

I've read diatom filters help and that they don't. So, I don't want to spend the $$.

I've read a lot about chemicals to add, but I don't want to do that either.

I'm hoping it will clear if I'm patient and diligent.

Any information or suggestions would be helpful.

Thanks,

Kathy

Sarah84 · 04-26-2007, 02:33 PM

Hi Kathy
Green water is a algea bloom, water changes water changes and more water changes, I have never experienced this myself.. you need to lower your nitrAtes and water changes will do that. Do extra vaccumming of the gravel.. cut down on the feeding like you have, and the light..
good luck let us know how it goes.. it will take time to rid this problem
sarah

Viper · 04-26-2007, 06:15 PM

Welp, i hope you dont have all the fish you listed in that on 30 gal tank, cause gold rule is 2 inches of fish for every 10 gal(or somthing to that effect), to many fish will cause nitrates and phosphates to go up cause of the waste produced by the fish, to kill the bloom you will need to do water changes, 20% every few days and leave the lights off for approx 3 days, then slowly bring the lighting back only have it on for 4 hours a day for about a week, you should only have your lights on for a max of 8 hours a day, or your tank will alege bloom again. i know what your battling ive been there also and green water sucks big tyme!! hope this helps.

Kathy · 04-26-2007, 06:33 PM

Sarah, thanks. I thought water changes would be the key but my freshwater fish book said don't change the water, didn't say why though. So, I'm off to do more water changes in the coming days.

Viper, thanks. Well I did say I was guilty of overstocking, and yes all those fish are in the tank.

Thanks for the advice on water changes and the lights, I was kind of halfway there on my own. Your experience will be helpful to me.

Maybe someday another 10 or 30 gal tank, or a 55 gal.

I already have 2-10's (with guppies, swordtails) and a 5 (with mollies and platies) along with the 30. I'd move fish around but all all stocked to the max.

K

BJP · 04-26-2007, 09:49 PM

If the tank is used to regular water changes then I'm not scared to give the tank huge water changes. I rarely change less than 100% at a time. it's pretty simple actually. Once your tanks are accustomed to larger changes which you can work up to gradually, vacuum about half to 75% of the tank water out, add a hose with temperature adjusted water then match the incoming flow to what's leaving. The remaining water gets flushed out gradually with the flow.

No algae left, no nitrate left, no phosphate left. (assuming the new water is free of those)

If it comes back the next day or two when you know the nitrate and phosphate is still low then you can be certain you're dealing with a lighting or silicate issue with lighting being the most prevelent and easiest to alter.

As for some of your other thoughts, API offers a phosphate test kit, diatom filters would work but they really aren't needed here, chemical fixes can blow up and cause secondary problems even worse, UV would work but that's another $100+ solution for a UV and pump that a simple large water change could accomplish easily, towels and blocking light can kill off the algae but then it can decompose and shoot the ammonia off the chart as well as shooting the nitrate back up (better to rid the tank of it in my opinion with the water change) then the base ingredients are still in place to feed a recurrence, and with your stocking level I would also think a larger tank would be in order soon or at least converting your original tank to a continual flow setup so the water changes never actually stop. A slow trickle entering the tank all the time, the extra leaving through a drain. No more nitrate, phosphate, green water, ammonia, nitrite or accumulation of DOC's and GH. As a side benefit your PH should stay stable and the KH should never get depleted. An extra benefit is you can feed your fish a normal healthy diet as oppossed to minnimalizing the diet chasing low numbers.

Jay · 04-27-2007, 07:48 AM

You will never get an argument out of me concerning the benefit of large water changes. I do a 75% weekly without fail.

Regards,
Jay

SailorMi · 04-30-2007, 12:44 AM

I had a alge bloom in my 20 Gal tank. This tank is located in the basement and probably gets a lot of light thru the small windows about 20 feet away. Frequent 50% water changes helped temporarly, but it kept returning. Prior to going on vacation I reduced artificial lighting from about 16 hours to about 4 hours per day. When I returned 1 1/2 week later, not a trace of alge bloom.

No alge bloom in my 55 Gal tank, however the water was always cloudy. In addition to the artificial light, the tank was getting a lot of indirect light thru a curtain next to the tank. Closing the mini-blinds on that window and reducing the artificial light from about 16 hours to about 4 hours did the trick.

Now I leave the light on each tank for 7 hours per day and both are clear.

Rex

Kathy · 04-30-2007, 01:51 PM

Thanks everyone. Sounds like water changes are the key, so I'll keep those up, maybe do closer to a 50% every couple of days until the water clears. Have been keeping the lights off, it's been about 6 days now, and that is also helping the water clear. I can see deeper into the tank, and see the fish again!

K

Sarah84 · 04-30-2007, 05:10 PM

good to hear!!

Sarah

Kathy · 05-03-2007, 07:42 PM

Did a 50% water change yesterday, nitrates down to 40 now, planning another water change tomorrow. Water seems to still be clearing. Still keeping the lights off.

Lost four otos to the high nitrates and never knew they were missing in the algae bloom, the other fish cleaned them up. Also lost the one tiger barb.

Now for the good news, in a different tank my guppies are having babies!

K