Algae scrubber won’t grow - any ideas why?

[djryan2000]

I purchased a Santa Monica drop 1.4x 6 months ago. I first ran it for 24 hours and saw no growth so I dropped it to 20, per the instructions. The algae started to grow and stripped my tank of phosphates. I started dosing phosphates and then upped my feeding significantly as I got a captive bred dragonet a month ago. I no longer dose phosphates as the feedings keep it up. Despite the increased feedings and nutrients, the algae scrubber is making no progress. The slime coat it had a month ago has even disappeared and I’m not sure what’s happening. Here’s a pic

I run the lights 20 hours daily and there’s an air pump connected 24/7.

 

[sp1187]

I've got a SURF4X from them. I'm running mine directly opposite of my display lights schedule. (11 hours on, 13 off) I mostly have very good growth in mine. but there are times where I don't have as much. I've taken to buying a small amount of chaeto from the lfs and tossing that in.

 

[AZMSGT]

20hrs is far to long For light. But presently.. Are you sure the light is functioning? Not familiar with the santa monica scrubbers.

 

[djryan2000]

20hrs is far to long For light. But presently.. Are you sure the light is functioning? Not familiar with the santa monica scrubbers.

Yup, I just took the photo when the red lights are off. What do you recommend for a photo period?

 

[sp1187]

invisible ink

 

[laverda]

My guess is you depleted you iron as well as your phosphates. Iron is needed for algae’s to grow in very small amounts. It typically should not be detectable4 hours after dosing with most hoppy test kits.

 

[AZMSGT]

Most people with algae scrubbers run them at the opposite time as the lights. So if your lights are on 12 hrs a day then the opposite 12 is when you run it. However it it’s sucking your system to clean then adjust the photo period. Run only 8, 6, 4 or 2hrs to control your system. It’s not a set it and forget it process.

I ran a scrubber for about 6 months. Once my corals started to consume my systems nutrients more and more I would adjust my scrubbers photo period till I got to the point when I shut it down.

 

[Devaji]

what are your Po4 levels? looks like a small tank? how often are you doing Wc? I am guessing you dont have much to remove and with 20hr i bet its burning up anything.

I would drop it down to 10hrs and start there and see what happens.

 

[djryan2000]

My guess is you depleted you iron as well as your phosphates. Iron is needed for algae’s to grow in very small amounts. It typically should not be detectable4 hours after dosing with most hoppy test kits.

Thank you. PO4 is still up, around .1 ppm but I have no clue about iron. I have been doing regular 25% water changes. My assumption is that the iron would be replenished. Is this incorrect?

 

[djryan2000]

what are your Po4 levels? looks like a small tank? how often are you doing Wc? I am guessing you dont have much to remove and with 20hr i bet its burning up anything.

I would drop it down to 10hrs and start there and see what happens.

PO4 is currently sitting between .1 and .14 ppm. I am changing water about once a week to reduce nitrates and try to keep alkalinity up until I get a functional doser.

 

[laverda]

Thank you. PO4 is still up, around .1 ppm but I have no clue about iron. I have been doing regular 25% water changes. My assumption is that the iron would be replenished. Is this incorrect?

Probably not. Depends on your salt mix. Even if it had normal levels of iron, it would take a lot of water changes to bring it back up. Iron would still being used between water changes. It is the same for doing water changes to reduce nitrates is not very effective. Assume your nitrates are at 100. Your first water change would make a big difference, reducing them to 75. The next 25% water change would reduce them tp 56.25. The 3rd water change would reduce them to, 42.19. 4th drops them to 31.64. After 5 water changes your nitrates should be 23.73. Each change has less effect. But this is assuming no new nitrates are being produced during this time. If just 10 nitrates were produced between each water change, you nitrates would still be at 54.24. So after five 25% water changes you have changed the equalivint of 125% of you water volume, but only dropped your nitrates 45.76%

 

[Cory]

Ime scrubbers just need two things. Excellent flow, and red leds. Make sure the flow is strong and working as normal and that the red leds arent too intense. Iron and manganese can help too but will come with food usually. If those are good, it could be not enough no3 and po4.

 

[Garf]

I purchased a Santa Monica drop 1.4x 6 months ago. I first ran it for 24 hours and saw no growth so I dropped it to 20, per the instructions. The algae started to grow and stripped my tank of phosphates. I started dosing phosphates and then upped my feeding significantly as I got a captive bred dragonet a month ago. I no longer dose phosphates as the feedings keep it up. Despite the increased feedings and nutrients, the algae scrubber is making no progress. The slime coat it had a month ago has even disappeared and I’m not sure what’s happening. Here’s a pic

I run the lights 20 hours daily and there’s an air pump connected 24/7.

I would scrub it totally clean with fresh water and a stiff brush and start again. If it worked first time, it should work again. However when you say it started growing, it stripped your tank of phos? It must have produced a lot of algae. This is one of his hubbly bubbly scrubbers isn’t it, so flow may be a problem, as may be light intensity, as maybe screen cleaning. Yeah I know, that don’t leave a lot that’s right with it, does it.

 

[Hot2na]

How's your DT looking ? any nuisance algae ? if not - maybe you just don't have enough algae fueling nutrients..if so - then ramp down the tank lights and ramp up the scrubber lights ..it will take time but eventually the nuisance algae will grow mainly in the scrubber...NOTHING happens quick with a scrubber...

 

[Garf]

How's your DT looking ? any nuisance algae ? if not - maybe you just don't have enough algae fueling nutrients..if so - then ramp down the tank lights and ramp up the scrubber lights ..it will take time but eventually the nuisance algae will grow mainly in the scrubber...NOTHING happens quick with a scrubber...

I think these scrubber lights are on full blast, all the time. I remember reading posts from Santa Monica that said to reduce the light intensity you should cover some of the LEDs with gaffa tape, really!

 

[djryan2000]

How's your DT looking ? any nuisance algae ? if not - maybe you just don't have enough algae fueling nutrients..if so - then ramp down the tank lights and ramp up the scrubber lights ..it will take time but eventually the nuisance algae will grow mainly in the scrubber...NOTHING happens quick with a scrubber...

Very little nuisance algae in the DT. Nutrients are sitting with phos at .1ppm and nitrate ~25ppm, which is a little high for my liking. There’s a small patch of bryopsis that came on a frag and some bubble algae in a spot or two.

 

[Turbo's Aquatics Verified Sponsor]

My guess is you depleted you iron

Iron is highly reactive and difficult, if not impossible, to keep at detectable levels in a reef tank. I tried dosing iron once, it made minimal difference. I grow tons of algae and never dose iron. The only reason to dose it is a last ditch effort to get a scrubber established initially, and I don't even bother recommending that. Adjusting the photoperiod and/or intensity is #1 to getting a scrubber started when it is struggling

Ime scrubbers just need two things. Excellent flow, and red leds.

Agree

I would scrub it totally clean with fresh water and a stiff brush and start again.

I would not do this unless it is growing only slime algae, and that type of growth usually comes off with water flow from a faucet and gentle agitation. You can use a soft toothbrush to gently loosen that type of growth, but don't hard-scrub and reset - that'll just mean you're going to start all over again

On a side note, @Garf is that you from back in the day??

 

[Garf]

Iron is highly reactive and difficult, if not impossible, to keep at detectable levels in a reef tank. I tried dosing iron once, it made minimal difference. I grow tons of algae and never dose iron. The only reason to dose it is a last ditch effort to get a scrubber established initially, and I don't even bother recommending that. Adjusting the photoperiod and/or intensity is #1 to getting a scrubber started when it is struggling

Agree

I would not do this unless it is growing only slime algae, and that type of growth usually comes off with water flow from a faucet and gentle agitation. You can use a soft toothbrush to gently loosen that type of growth, but don't hard-scrub and reset - that'll just mean you're going to start all over again

On a side note, @Garf is that you from back in the day??

Yes indeed bud.