Tropical Fish Keeping - Aquarium fish care and resources

Tropical Fish Keeping - Aquarium fish care and resources (
-   Beginner Freshwater Aquarium (
-   -   what lighting to reduce blue-green algae? (

VicA 03-01-2011 08:54 AM

what lighting to reduce blue-green algae?
I have a Jewel 180l aquarium, partially planted (java fern) and I'm having terrible problems with algae. I get the normal stuff on the glass which isn't so much of a problem (cleaned off with weekly partial water changes) but I also get thick slimy dark green algae that carpets the sand, plants and wood. I'm wondering if I need to change my lights - I currently have 2 fluorescents, a 'Sunglo' lamp (210 lux, 4200K) which it says is suitable for freshwater aquariums, and a 'Aqua-glo' lamp (120 lux, 18000K), suitable for freshwater and planted aquariums. I think they are Arcadia brand lamps.
Should I change them? If so what for?

DDiscus 03-01-2011 09:03 AM

Not sure bout lighting, but I have had same problem and I treated it with Eryrhtomycin and it has not been back since. Took like 4 treatments and some water changes..

VicA 03-01-2011 09:08 AM

thanks, but I'm in the UK so I don't think getting the anti-biotic will be an option over here.

Byron 03-01-2011 10:59 AM

Before considering "treatments" (which can often have side effects on the fish or bacteria or plants), you need to find the cause; otherwise algae and cyanobacteria will often return.

Algae is caused by light. However, what you describe as the slime coating gravel, etc. is not true algae but cyanobacteria. This is caused by organics in the presence of light.

You have a 180 litre tank (approx 50 gallons for those of us who "think" Imperial:-)) with two fluorescent tubes. Java Fern is the only plant you say; this will tolerate fairly low light, and is slow growing, which means it is not going to assimilate a lot of nutrients (from organics). Plus, as it is not rooted in the substrate like some plants, the detritus building up in the substrate is not getting used and the resulting organics leech into the water column. Overfeeding can also contribute, so have a look at that. Plus, the fish load; how many fish and what are they?

The light is adequate for Java Fern, but other plants would have a struggle. Excess light will feed algae. How long is it on each day? Is there much room light (from windows, etc.)?

Knowing the above will help us with the solution.

And, welcome to Tropical Fish Keeping.:wave:


aunt kymmie 03-01-2011 11:13 AM

Welcome to TFK! I agree with Byron. I have also battled the dreaded cyanobacteria and finally was able to get rid of it. Don't use antibiotics to kill it as it will nuke your biobed and I see you have fish in your tank. As Bryon states excess organics and light is what BGA feeds off of. I removed as much of it manually as I could, changed my lighting and started using Purigen in my filter (to suck up excess organics) and that seemed to solve the problem. What are your water parameters? Curious as to your nitrAte level. How often do you perform water changes and at what percent when you do your water change??

VicA 03-01-2011 11:21 AM

Hi , thanks for the welcome. Fish wise I have 3 rams (2 german blue, one golden and yes they get on ok lol), 4 small corys (1 peppered and 3 punctatus), 8 neon tetras, 8 silvertip tetras, 8 golden tetras and 2 cherry barbs.
Currently the lighting is on from 8am to 10.30pm. There is some natural light from a nearby window but I wouldn't say a huge amount. I've just reset the lighting timer to go off earlier - is this a good idea?
Substrate is sand.
I have an air disc buried in the sand which having read that lack of water movement can be a factor I'll now run full time (it hasn't been on full time recently). I run 2 filters - the internal Jewel filter that came with the aquarium, and an external Fluval 105 as well.
I've spent some time this afternoon cleaning more (I did a bit of a clean and a 50l water change on Sunday), removed most of the internal decorations (2 plastic plants, 2 of the smaller bits of bogwood, 2 ornaments and many small rocks) and given them all a thorough clean and suctioned the worst of the detritus off the sand underneath. On the next water change in a week I'll take out the really big bit of bogwood out and clean that and the sand underneath it (didn't want to stress the fish too much by doing it all in one go!).
Checked water parameters before cleaning today and ammonia and nitrite are zero with very small amount of nitrate (bearing in mind there was a water change only on Sunday).
I usually change around 40l when I do a tidy up and water change, usually every 7-9 days.

Byron 03-01-2011 11:34 AM

No surprise here. You have a lot of fish for a 50g (especially with no high-nutrient feeding plants), and the light is on much too long. You will have continual trouble with algae and/.or cyanobacteria until this is changed.

First, the light. No more than 10 hours on per day, ensuring there is total darkness (=no daylight, no room light) for about 10 hours each "night." Reducing it even further at first would probably be good, down to even 6 hours until things clear up. Use a timer so you can set the "on" to when you are normally there to view the tank. Fish and plants don't care when they have light and dark, so long as it is relatively stable.

Second, more plants that will use the organics faster. Swords (Echinodorus species, pygmy chain sword) are good because they are easy-care (like the Java Fern). Stem plants are good, but they need regular trimming/pruning and require more light.

Which brings me to the light. If you get more plants, I would change the tubes. "Daylight" tubes with a kelvin around 6000K-7000K work best. You can buy these in hardware/home improvement type stores. Measure the length of the present tubes (minus the prongs) and look for that size in tubes made by GE, Phillips, Sylvania that have a kelvin rating around 6500K.

Also, liquid fertilizer if you increase the plants. Organics will not provide everything, and plants can only fully photosynthesize if they have all the nutrients and light. Seachem's Flourish Comprehensive Supplement is one I recommend. It is a fact that adding nutrients--provided the light is in balance and there are sufficient plants to use all this--actually works to decrease algae. The higher plants out-compete algae.


VicA 03-02-2011 04:23 AM

ok thanks, I will endeavor to get some pygmy chain swords, some plant food and change the lights. I'm aware there are a lot of fish (hence 2 filters) and as they reach the natural end of their lives they won't be replaced. I'll see if I can find seachems in the UK.
I've reduced the lit hours down to 8 hours too.
Fingers crossed!

All times are GMT -5. The time now is 09:21 AM.

Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

For the best viewing experience please update your browser to Google Chrome