How to prevent greenish water in tank placed outside?

**eric6363** · 28th Apr 2011, 09:54

After reading some horror stories about tank leaking or breaking and flooding the living room, I have placed my 2 fresh-water tanks outside in a sheltered area. However, the water turns green within a few days.

Is there anything I can do to prevent the water from turning green? I already have sucker fish in each tank, plus UV light. Thanks in advance for any advice.

**equidorz** · 28th Apr 2011, 21:06

If you have direct sun shinning at your tank, green water bound to have.

**Kiatster** · 28th Apr 2011, 21:49

More powerful UV light attached inline with canister filter for three days.

**ZackZhou** · 28th Apr 2011, 23:24

More powerful uv light!

maybe the 30w one selling at c328?

**hayabusa** · 2nd May 2011, 03:20

try to place it in a area with less sunlight or you could do like the rest suggested with a uv light.

**Shadow** · 2nd May 2011, 08:43

how many watt is your UV? how strong is your filter flow? higher flow rate require higher UV wattage.

**comet** · 9th May 2011, 15:59

Hmm, possible to use a heavy plant load. Lots of floating plants and other fast growing plant. Worth a try. But of course, the bio load of the tank must not be too high.

**eric6363** · 26th Jun 2011, 23:29

Thanks guys for your replies. Bought 2 x UV filters 36W each, will let them run for a few days.
Also bought 2 x 3-feet LED blue lights - very nice blue glow at night.

Also bought an external filter which comes with UV light from Jebao for my 6-feet x 3-feet tank.

**stormhawk** · 27th Jun 2011, 01:17

Remove the sucker. If you have the normal Pterygoplichthys gibbiceps sucker, then it is aiding the green water from the poop it produces.

UV light can only do so much if you do not keep the nitrates down. Get some hornwort or some other fast growing plant to suck up the available nutrients. If the tanks have no other fish, you can consider using Daphnia/Moina to clear up the green water. Alternatively, I guess covering the tank in a black trash bag for some days should help. See this site for more help:

http://www.aquariumalgae.blogspot.com

**eric6363** · 28th Jun 2011, 09:15

The tank is almost cleared after 24 hours of UV light treatment, will let it run for another 24 hours.
Half of the LED, however, have dimmed. Both tubes are the same.

**Blankies** · 28th Jun 2011, 23:36

wah....UV light really kills the algae eh

**stormhawk** · 28th Jun 2011, 23:38

Only the spores and those algae that are still in suspension are killed. It will not solve the issue in the long run, but good as a "preventive" method. Replacing the UV tubes can get costly.

**Blankies** · 28th Jun 2011, 23:40

Will the UV light have any negative impact?

**stormhawk** · 28th Jun 2011, 23:46

No negative impact as far as I am aware of. Only danger arises if the UV filter is broken and the light gets short circuited in the water.

**eric6363** · 29th Jun 2011, 09:21

I am happy to report that, after 48 hours, the water turns from green-tea-cloudy to crystal-clear.
The blue LEDs, however, have definitely dimmed on half of each of both tubes - I will have to bring it back to exchange.