[calankh]

I need some advice on algae control. Will give a brief history of the tank, it has been set up ~5 months. Current stock is a betta and a couple mystery snails.

TLDR version: added finnex light, have green dust algae issues. followed instructions to leave it alone, but a month later it's gotten really bad. do I have too much light?

I have a Fluval Spec 5, with red fluorite substrate. I set it up with some java fern, java moss, an anubias, some crypts. Aiming for an easy no CO2 setup with few water changes as it's a tank on my desk at work and I don't have time for that. The water was pretty soft and I wanted to keep snails, so I dosed with equilibrium to try to bring up the calcium. That didn't work very well, so I added some aragonite sand, which fixed both my low pH problem and the soft water. Snails seem quite happy. I have not added equilibrium since probably February.

Then I decided the light was too dim. So in early March I upgraded from the stock light to a 16 inch Finnex FugeRay Planted+. And my plants didn't grow, but boy the algae has. I tried adding an extra snail, and that keeps it off the walls pretty well. But it's coating all my plants, and they don't seem to be growing (they weren't with the low light before either but I think they are actually dying under the 1/2 cm of algae on all the leaves).

It looks like a lot of green dust algae--I can't even see the java moss anymore, and most leaves have a pretty thick coat. The algae guide said to leave it alone but it is just getting worse. I'm nervous about messing with the chemistry of a tank this size, as I know they are more fragile than the larger tanks I'm used to.

Is this just too much light for a tank this size? I'm not dosing with anything else, was hoping to set up a lowtech, low maintenance tank for work but I seem to have achieved algae heaven. If I need to step back the light, what light would you recommend? I'm not opposed to swapping that out, I can use the high powered one to do a dedicated plant tank at home, where I can play with parameters more.

Any other advice would be greatly appreciated.

 

[rancidcrab]

Having the same light and tank as you, but running CO2 and dosing a high tech setup, I'd say you have too much light for the plant load you are running. I think the stock light could handle it. You need to cut back the time that you run your lights or do some research on adding a dimmer to the lights. I also dose glut (excel) to help control algae.

 

[calankh]

thanks rancidcrab! I realized after writing all that up that dosing excel might help. Had forgotten about it as an option. I did dial my lighting time back lots (from ~13 hr stock light to 2 4hr blocks with the finnex). I also swapped back to the stock light this morning, but it's so dim I can't really see the tank very well, so I don't think that's a good long term option--no point in having the tank there if I can't see it!

 

[rancidcrab]

Are you comfortable with some DIY electrical work? Splicing in a dimmer would be a good compromise between the crappy stock light and the intense finnex. If you're brave enough you can even use a TC420 as a timer/dimmer to control the red, blue and white channels of the LED.