Dark Green Coating

[neon]

I am wondering if anyone can suggest what I can do about a dark green coating I get all over my plants.  Its like algae, is a dark green, and dosn't rub off very well.  My plants get coated in it and the leaves eventually rot away, I guess because they don't get any light because of the coating.  My lighting is very good, I have a 54 gallon with a coral life double strip fixture.  I was thinking I would have to replace the bulbs, they are about a year old.  I do regular water changes, once a week.

[fischkopp]

It sounds like the leafs are covered well under green spot algae - especially older leafs in full liht should be affected, right?

If this is the case, then the cause is very likely low CO2 in conjunction with low phosphate levels. Do you add any fertilizer or CO2 to your tank?

ps: reported to move into planted section

[neon]

I do add fertilizer, but no CO2. 

[Fishnut]

It sounds like the plants can't absorb enough nutrients to keep the algae away, so the algae is thriving on what the plants aren't absorbing.  Adding CO2 would allow the plants to be able to absorb more nutrients (I think), but also reducing the amount of nutrients in the tank will help control algae.

What kinds of plants do you have in the tank?

[neon]

I have Java Moss, a crypto something or other, some very long grass like plants, and an Anubias.  The anubias and the grass seems to be the most affected.  The moss and the crypt are fine. 

[fischkopp]

It sounds like CO2 is the limiting factor that allows your plants to outcompete algae. Fishnut is right that increasing the CO2 level will allow the plants to absorb more other other nurtients, until on of the four light, CO2, Macronurient and Micro nutrients become the bottleneck again.

I dont think that reducing the nutrient amout will help you much, given the light you are using. Maybe reduce the ligthing duration to 8-1o hour as a first step. If you dont see much improvement after a couple of weeks (or your light duration is already short) then you may try liquid carbon sources like Seachem Excel or even DIY CO2.

[BigDaddy]

Lets start off with some basics first.  What are the dimensions of your 54 gallon and what kind of lighting and how much of it do you have over the tank?

What fertilizers are you adding and how often?

[neon]

My 54 Gallon is a bowfront, so it is fairly deep.  I have my lights on from about 7 am until about 9 pm.  I'll start turning them off earlier.  I dug out an old Red Sea C02 canister that I had and wasn't using, I'll get that going tonight.  This might improve things.

[BigDaddy]

Okay.. we need some DETAILS though.  How many watts of light do you have, and what type (fluorescent T5, T8, T12 etc... , compacts, metal halide etc...)

As well, what type of fertilizer and how often do you dose

What are the physical dimensions of the tank?

fischkopp is likely right about the spot algae, and Anubias is very much susceptible to it as a slow grower.  You are better off not putting those in direct light otherwise you'll definitely get spot algae on them

[charlie]

Neon , did you not have similar issues of too much light & no co2?, might have been a different algae, but the same basic Principal applies, anything over 3 WPG ( at times over 2.5 WPG) & carbon supplement becomes a MUST, how ever you choose to supplement it is up to you, there are several ways available.

If memory serves me right , you were using a double 36 inch 96 watt ( total of 192 watts) fixture at the time , if you are using the same fixture you have about 3.5 WPG.Which is a whack load of lights on a 54 gallon more so with the plants you list. In as far as nutrient requirements for planted tanks go ( again on the assumption that you are using the 2x96 watt) , you defiantly have the first one in the chain of command covered ( Light) , you need to balance the other 3 - carbon, macro nutrients & micro nutrients, oh you need to reduce your photo period to about 8 hrs for starters.
Regards

[neon]

Good memory.  Yes, I am still using the same lighting.  I'll start turning it off when I get home and I am going to start using the co2.  Thanks.

[CrazyFish]

I came across this article today that might be useful. 

http://www.otocinclus.com/articles/algae.html

You might also find this site useful:

http://www.rexgrigg.com/Algae1.html