Algae Removal

Yahtzee170 · Feb 17, 2020

I have a Red Sea Reefer 170 (34 gallon display) and have been battling an algae outbreak. The tank is about 2 years old, but had been neglected. I've taken photos for the past few weeks and haven't noticed any algae growth but I'm also not noticing much improvement.

What I'm doing so far:
Cut feedings to small amount of pellets twice a day (fish consume all in ~15 seconds)
Testing weekly (Calcium ~425, Alk ~8.5, Mg ~1425, Salinity 34.9 PPT, Temp 78.8, Nitrate <0.5, Phosphate 0.01-0.03)
Manual removal with siphon weekly
Added algae scrubber
Added clean up crew (28 dwarf ceriths, 11 nassarius, 12 florida ceriths, 11 nerites, handful of hermits)
5 gallon water changes weekly

I'm struggling to remove the algae entirely from the rock. It tends tear and I'm not able to siphon a short section out. I've tried scrubbing with a toothbrush but even that doesn't remove it easily.

Here are the photos:
1/7/20

1/25/20

2/15/20

How quickly should I expect the clean up crew and scrubber to make a difference? Anything I should be doing differently?

Turbo's Aquatics · Feb 19, 2020

Pics of scrubber? How long has the scrubber been running?

Yahtzee170 · Feb 19, 2020

Turbo's Aquatics said:
Pics of scrubber? How long has the scrubber been running?

Scrubber has been running for 1 month. Will grab a picture tomorrow morning, but so far just small amounts of a yellow-green slime.

Turbo's Aquatics · Feb 19, 2020

If you haven't done any sort of cleaning yet, take the screen out and swipe it with the palm of your hand while running under room temp tap water.

The slime type growth gets going first (more primitive type of growth) and has a tendency of preventing GHA from getting a foothold, so you want to clear that type of growth off as often as 2x/week until GHA starts to fill in.

As for the rest of the system, if it has been neglected, then making a correction (i.e. being more aggressive towards nutrient removal) can cause those nutrients that have been sinking into the rock to become more available (i.e. coming out of rocks) and that's where algae becomes opportunistic. It might take some time for all the nutrients to get liberated from the rock.

Yahtzee170 · Feb 20, 2020

Phosphate 0.003 and nitrates close to 0 today. Water change due in 2 days and will manually remove again.
Long term I don’t want nutrients this low, but until I get algae under control is it reasonable to keep them there? Do I need to worry about things like dinos or anything else?

Turbo's Aquatics · Feb 20, 2020

Ok, that's an upflow scrubber. I don't have any experience personally with that particular type of upflow

Yahtzee170 said:
Long term I don’t want nutrients this low, but until I get algae under control is it reasonable to keep them there?

You can allow nutrients to raise up a bit, if it was neglected to the point of something much higher then anything that is significantly lower is the right move. So (just for example) if you had 40ppm nitrate and 0.5ppm phosphate, lowering both of those to 20% of that will get things moving.

If you run very aggressive nutrient removal, you can run the risk of altering the bacteria structure of your tank, and then when you remove that mechanism or back it off, the bacteria aren't conditioned to sustain the bioload and would have to build back up. That's why you make slow changes over time.