Algae/nutrients--help needed

[B Considine]

I'm fighting some serious BBA and thread algae in my 30 gallon. From Kris' article, it seems I need to bring my nutrient levels into balance. But how do I know what said levels are so I can adjust them? Can they be discerned through the usual water tests (e.g., pH, ammonia, nitrate/nitrite)? Do I need some further tests?

Originally, before joining GWAPA, I had serious BBA which I successfully resolved with more frequent water changes, upping light levels, and Excel.

But now I change 4/5 gallons 2 or 3 times a week. And I haven't resolved a thing. I've been using RO/DI water from work, then adding half the recommended dosage of Flourish.

Fish load is high. I run a 2213 as a bio filter only and an Aquaclear 70 with sponge, carbon, and ceramic noodles. Lighting is on 10 hours/day.

My most recent water stats: pH 6 (yikes), ammonia 0, nitrate 0, nitrite 0 (based on an API match the color type test). Don't have a water hardness test.

Any advice appreciated. Would prefer to save up for pressurized CO2, but I am willing to try DIY as a stopgap.

Blaise

[krisw]

The only other test that might be interesting at times would be for Phosphate, but from what you tested already, the 0 nitrates is the reason you have BBA. Do a water change, and dose a bit of nitrate. Not a lot since you're not using CO2. Is it possible your lights are too intense for no CO2? Also, do you have spot algae on the glass? A little P should help that.

My suggestions would be (in this order):

- Keep up water changes
- Make sure circulation is adequate to areas where algae appears.
- Reduce light levels
- Dose enough N and P to sustain small amounts in the water column. (5ppm for N, 1ppm for P)

[B Considine]

Kris,

Thanks for the input.

Lighting is a single Coralife T5 strip. I did replace the Colormax bulb with a second 6700 when doing my annual bulb change in April.

I'll add a slight amount of Nitrate with my next water change.

No spot algae (but perhaps my fleet of ottos or nerites are taking care of that). Just annoying BBA and even more annoying and invasive thread algae.

Blaise

[Cristy Keister]

Excel is a good way to kill the BBA, which is probably what killed for you it last time.

[B Considine]

I dose Excel daily. Probably overdose daily. It's my sole source of carbon.

[krisw]

Blaise, the difference between dosing Excel, and dosing Excel to kill algae, is that for the algae, you often want to shut off your circulation, and use a syringe to squirt the Excel directly on the BBA. H202 works as well, but if the source of the problem doesn't go away, these are only stop-gap measures. Do not excessively overdose with Excel, particularly with soft-skinned fishes like Otos in the tank.