Cyano/Diatoms with no phosphates and low nitrate?

[BornToHula]

Sorry in advance for the long post but I am getting desperate to find a solution - my wife is NOT happy when the tank we have spent so much time and money on doesn't look good!.

Over the past month and a half I have had a major outbreak in Cyanobacteria and Diatom algae that is getting out of control. I am having very little success in attacking the problem, so I thought I would list my maintenance schedule and system specs in the hope that someone on here can give me some idea on where I am going wrong or what I need to do differently.

Over the past month I have been testing twice a week using Red Sea test kits for phosphate and nitrate. I always gets results for 0 ppm of phosphate and between 0.25 and 0.5 ppm for nitrates.

Alk is being maintained at 9 dKH using BRS two part dosing everyday

Ca at 450 ppm

Mg at 1350 ppm

pH ranges from 7.9 to 8.1.

Salinity maintained at 1.024

Some info on my system:

I have had the tank since the end of May, but prior to me purchasing it from user melloyello here on ARC, it had been up and running for about 2 years.

• 75 gallon tank with a 20 gallon sump, 80 lbs live rock, approx 2 inch sand bed (added in May/June of this year)
• 20 gallon water change every 10 to 14 days - using Red Sea salt. I try to siphon out the sand and scrape out any algae I can with a toothbrush when doing water changes.
• Neptune apex used to control temp at 77.4 to 78.0 degrees
• Vortech MP40 usually set to around 50% power, MP10 set to around 80% power - both controlled through the apex so the percentages change some throughout the day.
• 2 AI Sol Blues - on for 10 hours a day, output set to rise from 10% up to 75% which it holds for 8 hours then back down to 0 % at the end of the day.
• Reef Octopus 150 skimmer - seems to be skimming property and is emptied every few days
• Bulk Reef Supply dual GFO/Carbon reactor - BRS media changed every two weeks.
• Bulk Reef Supply RODI unit - all filters/resin replaced a month and a half ago and is reading 0 TDS. Membrane was not replaced when I changed filters.
• Small ~5 gallon in sump refugium with live rock rubble and Chaeto algae

Stocking list:

• 2 Clowns
• 1 Chromis
• 1 Kole tang
• 1 Watchman Goby
• 1 Red Velvet wrasse
• 1 Black Cap Basslet
• 2 red bubble tip anemones, 4 green bubble tipped anemones
• 1 fire shrimp, 1 pistol shrimp, 2 peppermint shrimp (will be going back to store when I can catch them, they have been attacking my frogspawn)
• Mix of LPS, Zoas and SPS pieces- all seem to be doing well. Lots of green star polyp as well.
• New maxima clam purchased last weekend
• Reefcleaners.org clean up crew with hermits, some reinforcements are being shipped to me today.

Something is obviously causing the algae to grow, but I am not sure what. Does anyone have any suggestion on attacking attacking the problem, or changes I need to make on my maintenance? Different or additional equipment needed?

Thanks for taking the time to read through this and helping a fellow reefer out!

[FarmerTy]

Do you have a picture you can post Hula? I don't see anything wrong with your parameters or maintenance routine.

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[BornToHula]

Ty, I currently only have this picture with me on my phone. It is about a month old and not very good quality, but you can see the start of the Cyano growing on the left side on the sand. It has since taken over that side as well as the right side's sand bed and many of the live rocks' surfaces.

I have better pics on my home PC I will try and upload them on my lunch break.

[jestep]

Did you reuse the sand or start fresh? Also, what and how frequently do you feed?

If it's cyano, chemiclean will definitely get rid of it safely. But I would still want to figure out the cause and not just fix it without understanding why it's showing up.

[lenver]

I use chemiclean both times my system got cyano and haven't had any issues since, for what you're saying I think the tank is going thru it's normal maturing phase, diatoms usually just go out on their own, but yeah something might be feeding them, use chemiclean to kill it and see what happens to the diatoms, keep an eye out if any other kind of algae start to take their place

[FarmerTy]

My initial impression is just new tank syndrome. It's going to go up and down after the initial cycle for the first 6 months to a year as you continually add corals and fish, increasing the bioload. I just see this as your tank finding it's balance. You're near the 4-month mark if I'm correct. Time will take care of it as the silicates in your sand will be consumed entirely and the diatoms will go away.

As for the cyano, try to get more flow in the spots that it is getting a foothold and keep doing what you are doing with sucking it out with each water change.

I don't normally push red slime remover but your tank seems like a good candidate since your maintenance routine and parameters line up perfectly. In that, I can reasonably assume most likely it is not something you are doing but just the tank seeking balance. You can try to tip it in your favor by using the red slime remover to attack the cyano.

Tank is looking good from the picture and it seems like all your corals are happy. Just as a side note, as pretty as the star polyps are, if your intent is to not have a tank entirely covered by GSP, I would think about how to isolate it on its own island. It has a tendency to outgrow everything and cover all your rocks if you allow it to.

Best of luck with the fight against the diatoms and cyano. I think you are headed in the right direction!

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[BornToHula]

Did you reuse the sand or start fresh? Also, what and how frequently do you feed?

I started fresh with the sand. I used live sand - I believe CaribSea purchased from Aquatek.

For feeding I feed both pellets and frozen mysis.

If I am feeding pellets I feed with a feeding tool and usually very little hits the actual sand bed. However when feeding mysis, i cut a cube in half and melt it in RODI water in a cup. Then I slowly pour in the food from the cup into the tank. Some mysis definitely hits the sand bed when I feed this way, but I didn't think it was too much excess food. Perhaps I should cut back to a quarter cube?

Edited September 16, 2014 by BornToHula

[BornToHula]

Tank is looking good from the picture and it seems like all your corals are happy. Just as a side note, as pretty as the star polyps are, if your intent is to not have a tank entirely covered by GSP, I would think about how to isolate it on its own island. It has a tendency to outgrow everything and cover all your rocks if you allow it to.

Yes I am noticing that about GSP, in fact I had taken a couple of those rocks out and tried to scrub off the GSP - but it just came back bigger and stronger!

As for the cyano, try to get more flow in the spots that it is getting a foothold and keep doing what you are doing with sucking it out with each water change.

I have a couple of spare Tunze power heads I can put in to add more flow to the problem areas. For some reason I am always afraid of having too much flow in my tank though. If I put the MP40 and MP10 to full blast it looks like a hurricane is occurring in there.

[mFrame]

Did you reuse the sand or start fresh? Also, what and how frequently do you feed?

I started fresh with the sand. I used live sand - I believe CaribSea purchased from Aquatek.

For feeding I feed both pellets and frozen mysis.

If I am feeding pellets I feed with a feeding tool and usually very little hits the actual sand bed. However when feeding mysis, i cut a cube in half and melt it in RODI water in a cup. Then I slowly pour in the food from the cup into the tank. Some mysis definitely hits the sand bed when I feed this way, but I didn't think it was too much excess food. Perhaps I should cut back to a quarter cube?

Also try letting your mysis thaw in RODI, then strain it out (don't introduce the melted water into the tank, just the mysis).

Siphon out all the cyano you can. Follow up with three days of darkness followed by a water change of at least 25%. That plus the coming drop in outdoor temperatures will make the difference.

[victoly]

To echo others, sounds like some new tank syndrome with a bit of excess nutrients. Hard to say unless you pin down your PO4 readings a little tighter. My current favorite PO4 (by proxy of phosphorus) is the Hanna ultra low phosphorus meter. Good lab procedures are important to getting quality phosphorus readings. Here's a guide here:

http://www.austinreefclub.com/topic/31692-lab-procedures/?p=246894

[BornToHula]

Also try letting your mysis thaw in RODI, then strain it out (don't introduce the melted water into the tank, just the mysis).

Siphon out all the cyano you can. Follow up with three days of darkness followed by a water change of at least 25%. That plus the coming drop in outdoor temperatures will make the difference.

Ah I never thought about needing to strain out the melted water from the mysis, I will do that from now on.

Would three days without light have a negative impact on corals/anemones? I may try doing that, and if it doesn't work go the red slime removal route.

Thanks everyone for the input so far, here are a couple better pictures (but still not great) of my tank how it is today.

[jestep]

Also, you may want to back off on the lighting intensity overall. I have no idea how you're running 75% on those without bleaching everything. I can't get over about 25% on mine.

3 day blackout shouldn't hurt anything. If that doesn't work, I would go the chemiclean route but make sure to either add an airstone or take the collection cup off the skimmer if you do decide to do it.

[FarmerTy]

Just a quick note on why I don't bother rinsing my frozen food.

Randy Farley-Holmes, a reefing guru chemistry buff, has quantified the phosphate addition of the rinse water of frozen foods and calculated it at roughly 1% of the phosphate content of the food itself. So basically, rinsing the frozen food gets rid of 1% of the phosphate addition of your frozen food. To give scale, that 1% of phosphate added from the rinsed water to 100 gallons of water would bump the concentration of the tank up roughly 0.0003 ppm.

Quoted from Randy:

"That amount washed away does not seem significant with respect to the "in tank" target level of about 50-100 times that level (say, 0.015 to 0.03 ppm), nor does it seem significant relative to the total amount of phosphate actually added each day in foods (which is perhaps 50-1000 times as much..."

Here's the article he wrote for reef keeping magazine, for those that like to read the nerdy stuff.

http://www.advancedaquarist.com/2012/3/chemistry

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[BornToHula]

Also, you may want to back off on the lighting intensity overall. I have no idea how you're running 75% on those without bleaching everything. I can't get over about 25% on mine.

3 day blackout shouldn't hurt anything. If that doesn't work, I would go the chemiclean route but make sure to either add an airstone or take the collection cup off the skimmer if you do decide to do it.

Wow, I'm surprised at the huge difference we are running on intensity. I haven't noticed any bleaching on anything but I have only started adding coral about 2 months ago. Not sure how quick things start bleaching.

[Bpb]

Agree with others. Your equipment list and maintenance are spot on. I think Ty nailed it, and it's just that your tank is fairly new. Expect all manner of algae blooms to happen over the next 6 month to a year and just don't worry about it. 3 day lights out once a month or so will help and that will not negatively impact your corals, especially if you don't dive back in to full intensity right away

[victoly]

What about if you have a 29 gallon tank and not a 200 gallon tank

[Makena95GT]

Glad someone has posted about tackling cyano. My tank is getting overrun. But ive also been slacking with water changes and even at 5% my new light is bleaching my lone stick. I need to build something to hang it higher but thatll have to wait till at leeeaaast friday.

But a water change is finally in order today. 25% siphon out more cyano, scrub rocks

. Three day blackout. . Another water change.

[Reburn]

I'm going to echo Victoly. I have had problems with P04 in the past when my tank was younger. Using a Salifert test I thought my phosphate was 0 but after I got my Hanna I learned my P04 was actually 0.25.

I would see if you can get another member to run down your Readings specifically your P04 with a Hanna to rule out any faulty testing before you start changing things.

[+Grog]

I agree with a lot of the above. Wait, time helps. Flow on the bad spots helps. Make sure you are not feeding too much. A 3 day, lights out, will help. Should have no negative impact, aside from your own viewing and enjoyment. Consider it an investment in your viewing pleasure.

IMO: lots of little things add up, no quick-fix.

[BornToHula]

I really appreciate all the advice from everyone! I don't think I have ever been on a forum that has been so friendly and helpful to a relatively new member.

I have done a 20 gallon water change tonight (as part of my normally scheduled maintenance) and will be going lights out for 3 days starting tomorrow. I will probably do another 10 to 20g water change to help siphon out some more of the existing algae tomorrow as well.

If I don't see an improvement then, I will evaluate the options of dosing the red slime removal or perhaps just waiting it out for a while longer.

[PeeperKeeper]

This thread helped me too. Although I knew about the various reasons for a cyano bloom that were discussed here, it prompted me to check the flow in an area of my tank that recently started having a problem, and sure enough one of my powerheads wasn't running at full power because it needed to be cleaned. I pulled them both and did the whole vinegar soak, toothbrush scrub and they're much better. Hopefully I'll see some improvement over the weekend in that area.

Thanks to all.

[Makena95GT]

This thread helped me too. Although I knew about the various reasons for a cyano bloom that were discussed here, it prompted me to check the flow in an area of my tank that recently started having a problem, and sure enough one of my powerheads wasn't running at full power because it needed to be cleaned. I pulled them both and did the whole vinegar soak, toothbrush scrub and they're much better. Hopefully I'll see some improvement over the weekend in that area.

Thanks to all.

Ahh I should probably clean mine today too. Thanks for the idea

Im impatient so I only did a two day blackout. So far so good. Repositioned the powerhead as well and going to do another water change tonight

[nvrEnuf]

I've got a couple of things to add.

1. I didn't see a lighting time line. 30 minutes to an hour more or less can make a big difference. The only time I get blooms is when increasing my light schedule.

2. Even then my blooms are SHORT due to my algae scrubber.At risk of sounding like a broken record: algal scrubbers work 100% as advertised in my experience; took the skimmer out the sump 6 + months ago.

~JW

[Long]

+ on lighting. The wrong led spectrum can promote growth. When I had cyno a year ago I dimmed my LEDs 1/2 way and

Shorten the lighting time. Never ran my tank in blackout. But there are various ways to control cyno.

I also added a big cleaning crew. Tank is running great now.

[BornToHula]

Just a quick update on how the tank is doing - I think I am making some slow and steady progress on the Cyano fight...

I did a 3 day blackout after I had scrubbed the rocks with toothbrush and siphoned out all the Cyano on the sand bed. After turning back on the lights, the tank looked good in regards to the Cyano - hardly any was noticeable. However now with the lights back on I am starting to see some growth again, but not near as severe or fast spreading as it was before.

Some other things I have done besides the blackout:

• Two 20 gallon water changes since last Tuesday, with water already made for a third 20 gallon change tonight.
• Forgot to turn off RODI unit one of the nights and ending up cleaning my tile floors with about 30 gallons of purified water
• Had some reinforcements to the cleanup crew come in from reefcleaners.org - mainly Hermits and Dwarf Ceriths.
• Adjusted LED lighting from 75% intensity to 50% intensity. I haven't seen any difference in how the coral behave in the lower intensity so I may drop the intensity even more.
• Added a Tunze power head I had laying around to the rear of the tank to attempt to eliminate low flow area.
• Ordered a Hanna low level phosphate checker to get a more accurate reading on the phosphates - should be in by Wednesday

Some things may do in the future

• Reduce lighting time - I currently have the lights on for 10 hours. I may reduce it to 9 or 8 and see how the tank reacts.
• Adding a canopy - I have a couple of dogs in the house that track in a lot of dust that inevitably lands in the tank. I don't know if dust has anything to do with the algae at all, but it can't be helping. I'm thinking a canopy will help keep that dust out.