plants and algae

Question
i have a 10 gallon tank with 8 neon tetras and two cherry barbs. it is planted moderately well with the tank lights(two 5w 120V-60hz) on 6 hours a day. i dont know if i should extend the amount of time. i give the plants carbon dioxide and plant food on a daily basis, adding only 2-3 drops of each. the tank has been running for many months. recently some type of algae appeared. it is dark green and attaches itself at like a pinpoint to either the glass or my artificial log. it looks like a brush point and is very short, maybe 1/2 cm. they seem to be spreading, but not onto plant leaves.i dont know what type of algae it is. it is very difficult to remove manually. i currently have no algae eaters in the tank. i was considering a siamese algae eater but i heard they grow big and maybe otos, but i dont know if they eat this type. i would really like to have a siamese algae eater though. please tell me how to get rid of the algae and how long to keep the lights on a day. thank you very much in advance

Answer
Dear Tim,
It sounds like you may have "spot" algae. This is a type of algae that forms tiny green dots that are very hard to remove. It is very common in planted aquariums and usually isn't a great cause of concern. Most algae eaters don't remove this type of algae unfortunately. Usually there is not much you can do about it. But it is generally unharmful at least.

Now I noticed you mentioned it looking like a brushpoint? By slightly "fuzzy" you mean? This could be hair or beard algae...And that is something you do not want to allow to get out of control. Manuel removal as much as you can is best and reducing the amount of fertilizers usually helps. You can usually tell if you have hair or brush algae as it will soon form long and flowing strands that become thick almost like moss. This can take over quickly so be sure to remove it quick if you spot this in your aquatic garden.

The best algae eater I can recommend for you is Otocinclus catfish. Although they don't eat hair algae and may have a difficult time grazing "spot" algae off in my experience they do a wonderful job at keeping your aquarium and plants algae free. Their tiny size is a great advantage since they can effectively reach and graze the tiniest plant leaves without doing any harm to them. They also fit extremely well in small planted aquariums like 10 gallons. Otos enjoy being in groups and I think a trio would be a good place to start. The only problem with Otocinlcus is getting them acclimated properly to your aquarium's water. They have a reputation for not handling changes very well. But if you are careful when first introducing them to your aquarium, they will prove to be hardy and long lived little algae eaters. Acclimating them properly would be to float their bag in the aquarium with light off (to reduce it from heating the bag water) for 20 minutes or so. Then add half a cupful of your aquarium water carefully into the bag every 5 minutes or so. If it is easier, you can take the bag out and sit it in a pitcher. Once the bag is nearly full to overflowing you can consider the otos acclimated to your water's chemistry and gently try to net them out. Carefully scooping them out with a aquarium safe cup would be better though!

Typically a planted aquarium does well on 10-12 hours of good light a day. If your plants have been doing well on 6 hours a day for many months that is really something! But typically a 10-12 hour day is best for most plants.

I really hope this helps! If you would like to try to indentify the algae you have... Try visiting this website-
"http://www.floridadriftwood.com/algae_indentification.html"

I really hope this helps!
Best wishes and happy gardening!
Karen~