ok, i have no filtration in my betta tank, other than a 'filter pouch' thing that claims to help with reducing toxins and algae. i figured it couldn't hurt. anyways, the tank is about 3.5 gallons, with heater, gravel, 2 plants and 2 fake bogwood things. my betta (ice-man) seems to be perfectly happy, patrolling the borders, blowing bubble nests and eating anything i throw at him. the only problem is this darn algae. it's like a slimy coat that forms on everything in the tank. i've tried adding king british algae remover, which is supposed to supress algae, but it doesn't help. i wipe out the tank, and siphon off as much as i can, but i'd rather know what was causing it, to be honest! the tank's lit with a lamp for most of the day - could it be too much light that is the problem? any help gratefully received...

I don't know if you have real plants in your tank, but real plants will compete with the algae for nutrients. The cause of the algae is light plus nutrients (nitrate & phosphate being two of the biggies). If you leave the tank light off for a few days, that will help get rid of the algae (3-5 days should be good). To prevent it coming back, you can add more plants and do more water changes. You can kill algae on live plants by using a solution of chlorine bleach and water. 1 part bleach to 19 parts water. Only dip the plants in it for 2 minutes, then rinse extremely well, or rinse in water treated with a dechlorinating product. You can also kill the algae on your ornaments that way. Again, make sure to rinse very well before you put back in the tank.

Unfortunately, anywhere you have water, light and nutrients you have algae.

BTW, what colour is the algae you are struggling with?

IS it like actual green algea or just clear slime?

it is actual green slime, not clear...kinda gross actually...

huh... I'd love to help you but I don't really now what. Maybe you could try keeping a snail in so it can munch on the slime? Just make sure there is a lid on the tank if you do get a snail.

Is the algae that you have sort of a bluish-green colour, and strong smelling? If so, it could be cynobacteria.

Here is a description that I found on the web:


Cyanobacteria is a single celled algae and actually more a bacteria. This algae usually starts out on one spot (dark with low water flow) then vastly spreading throughout the tank. As all single celled algae can grow fast, this one is the fastest. In an optimal environment, this algae can double every 20 minutes.

The cause: high nutrients (nitrates) and bad lighting as well as a high organic content in the water.

end quote

I would suggest that you do some water changes to reduce nitrates and the organic load in the tank, and perhaps cut down on feeding.

I have also heard that erythromycin will control this type of algae, but unless the condition that have caused it are corrected, it will come back.