Suggestions for this algae

[nouse66]

I started running my first high-tech planted tank a few months ago and I'm currently trying to battle an algae outbreak and looking for advice. Things were going pretty well at first but I developed a leak in my co2 regulator and it was 2 weeks before I got a replacement. The tank ran for a couple of months with co2, then 2 weeks with no co2, and now I'm on week 3-ish of being back on co2.

This is in a UNS 45u tank with a Chihiros wrgb slim. I'm dosing easy green 3 times a week with a weekly 30% water change. I've measured a solid 1.0-1.1 ph drop from my co2 in moderately hard southern California tap water. My light is currently on 45% brightness (default color mix) for 7 hours. I cut it down from 70% for 8 hours when I had to go into no-co2 mode and was planning to ramp it up a bit more as algae subsided. Maybe not to 70% again but 45% seems low. Although I've had my stem plants bounce back fairly well, my buce, monte carlo, and staurogyne repens seem to be drowning in algae. There's new growth on those plants too but I don't seem to be winning the battle. A couple of days ago I added a few more plants for the middle section since the AR that was previously there mostly melted and didn't recover from a trim.

There's some standard green fuzz on my dragon stone that my amamo shrimp like to graze on but down in the foreground there's something more filamentous that they won't touch and I haven't been able to identify. I've trimmed it along with the monte carlo a bit but it comes right back in a week. Should I do a blackout? Dose with Excel? Try and power through?

 

[Dennis Wong]

The CO2 on/off period probably caused enough reprogramming in your plants that older growth has deteriorated and they will always attract algae in this state. New growth can be well defended and that is where you see portions of algae free growth. The solution is tedious but will work if you follow through - which is to replant new growth, and get rid of all deteriorated older growth (while keeping current parameters stable so no new reprogramming occurs).
Same steps as described below: but in your case its more serious because you have a lot of build-up of older growth by now
How do you control algae without algicides?

 

[Jeff Miotke]

That’s a bummer. From your description, it sounds like staghorn algae—usually from a CO₂/light/nutrient imbalance. And the imbalance has stressed and weakened the plants. In your case, you’ve already identified CO₂ as the cause and fixed it, so you’re on the right track.

You could treat with Excel or h2o2 or both(1-2 punch), which is effective on staghorn, or simply power through now things are fixed. If new growth looks health and algae free, remove and replant any leaves with staghorn, since it embeds in the leaf margins where chemicals can’t reach easily.

If new growth doesn’t look healthy then it’s likely that you haven’t corrected the imbalance.

I wouldn’t recommend a blackout—it just further weakens stressed plants. Focus on growing healthy plants, and not fighting the algae.

Hope that helps.

 

[nouse66]

Thanks for the tips! I’ll try to remember to post a pic when things are looking better.

 

[Koan]

Thanks for posting the question and the pics while you're fighting the outbreak!

Everybody goes through this and it makes everybody that reads these posts feel better, to be reminded (with pictures!) that they're not the only one this is happening to