After a battle spanning most of 2009, I am happy to report that the cyanobacteria plaguing my reef aquarium has finally been beat. I've been holding off on this post for most of the month of January, waiting to see if a relapse might occur. As it hasn't, I'm ready to summarize a struggle that occupied most of 2009 and how I finally won the war.
The biggest problem with a major algae outbreak in the aquarium is how demoralizing it can be for the aquarist. In the end, all the money and hard work we invest in this hobby is for the purpose of having a beautiful aquarium in the home. A tank overgrown with red slime is an eyesore, and after months of ineffective manual removal thoughts being to turn towards tearing the entire setup down, starting over, or getting out of the hobby altogether. The most important thing is to stay diligent, even if the process extends for months.
In this post I'll outline my thoughts around how the cyanobacteria formed in my tank, what methods failed to remove it, and how I finally succeeded.
What Caused the Outbreak The cyanobacteria began settling in around June of last year. I attribute this to a combination of overfeeding and the loss of a fish that I was never able to remove, leading to a spike in nutrients from decomposition. Additionally, I was having some serious detritus issues, lacking a proper way for exporting the organic matter accumulating within my tank.
Another mistake I made was not removing the cyanobacteria immediately once it began forming on the substrate. I was not aware of how tenacious it can be once it begins growing within an aquarium. Manually removing as much as possible as soon as it becomes visible within the tank should be the number one priority of a reef keeper.
What Didn't Work Most of my posts on this blog over the last half of 2009 involved various attempts at defeating cyanobacteria:
Rising Nitrates In April I started to note my nitrates rising. I replaced my RO filters, which needed to be done anyway, but testing revealed this wasn't the source of the nitrate issue. In hindsight it was more likely detritus build up and overfeeding leading to the rise in nitrates.
Zeolites, Purigen and AlgaeFix In June I tried reintroducing zeolites, to little effect on nitrates. I added Seachem's Purigen chemical filter media, which I believe helped stop the rise of nitrates, and temporarily reduced them. And finally, I tried API's AlgaeFix Marine, a chemical additive that was quite popular on the reef forums and supposedly could magic away any algae outbreak.
AlgaeFix did absolutely nothing against the cyanobacteria, and had only moderate success on the green hair algae. In addition, I noticed a die off in snails and some shrimp after two weeks of the recommended dose. I would not encourage use of this product, regardless of the positive things one might read on aquarium forums.
Bolstered Clean Up Crew In July I brought in a larger clean up crew to deal with the detritus buildup and hopefully stir up the sand bed preventing cyano from forming. A large number of these snails died off immediately, something I am inclined to link to the AlgaeFix additive.
Manual Removal By July I'd been reduced to manual removal, a process I performed at least twice a week for the rest of the year. Manual removal involved getting into the aquarium with my hands and a toothbrush, scrubbing the cyano off the rocks so it wouldn't overgrow corals, and removing large mats of the stuff from the substrate. Due to the decaying organic matter and constant water changes for removal purposes, parameters in my small tank were exceedingly hard to keep stable, and a number of corals were lost as a result.
Algae Filter and Vodka In October I converted my filter into an algae scrubber with Chaetomorpha macro algae. I think this provided a marginal amount of nutrient export, and definately boosted the population of copepods and other beneficial bugs in the tank. But what ended up being the miracle cure was the addition of vodka dosing.
How I beat Cyanobacteria I absolutely attribute the daily dosing of a small amount of vodka into my reef aquarium to the end of the cyanobacteria problem. Rather than butchering the explanation of how an organic carbon source like vodka effects an aquarium, I will link to an Advanced Aquarist article that will do a much better job:
For my dosing, I followed the regimen documented by Melev on his (infinitely useful) website. This schedule began with what was merely a drop of vodka per day, and built up to a full dose of nearly 1ml daily. By October 23rd I observed that nitrates, which had been close to 40ppm for the majority of 2009, had been reduced to zero. They have tested at 0 ever since.
I had long assumed that the nitrates were the primary source of fuel for the growth of the cyanobacteria. Confirming this, after the nitrates were testing at 0 I noticed the health of the cyano immediately decline. Once a very thick carpet of deep red coloration, it began to take on more of a browned out appearance, growing much thinner. Eventually it changed form, appearing as strands waving in the current rather than a thick mat covering the substrate. Manual removal went from a daily process to weekly, and eventually became completely unnecessary. By mid-December my tank was free of cyanobacteria.
Dosing vodka as a carbon source has cured my tank of nitrate issues, cyanobacteria and hair algae, and (indirectly) detritus build up. The corals, invertebrates and fish have never looked healthier, and I've been able to resume heavier feeding without issue. I would suggest researching this method for anyone dealing with nutrient and algae issues in a marine aquarium.
As a follow up to a post in April, I recently converted the Aquaclear filter into an algae tumbler. Stocked with a small amount of live rock rubble and a large ball of Chaetomorpha algae, lit by a 15 watt compact fluorescent light. After adding this Algae on Thursday, testing for nitrates has indicated that the algae is effective: test results dropped to <5ppm from 20ppm last weekend.
If this continues to be successful, I'm going to look into a smaller LED light source for a more streamlined look. The current fixture splashes some of the warmer yellow colored light into the tank.
Another issue I've been dealing with is dropping pH, which has dropped below 8 at least twice in the past month. I've responded by adding Seachem Reef Buffer every other day, and increasing my testing. I've been considering adding a pH probe to my controller to make monitoring easier.
I have made some small progress against the cyanobacteria, primarily through manual removal. And by manual, I mean scrubbing things with a tooth brush. The scarlet hermit crabs added recently showed absolutely no interest in consuming cyano, so I think we can safely say they are not to be considered an effective solution for those dealing with this problem. The snails that I added are doing well for the most part. Upon their introduction to the tank, Boris made his first appearance in months, immediately slaughtering a turbo snail and taking over the new, larger shell. Several other hermits followed suit.
Suffice to say, I could not rely on this half-assed janitorial crew to solve my problems. I half expect them to unionize and demand four day work weeks in the near future.
Although nitrates continue to test at or close to zero, my working assumption is that the algae is consuming these nutrients prior to testing. The rampant algae scrubbing I have been performing on a daily basis has led to a detritus build up that my filter capacity is simply not equipped to deal with. Regular turkey basting of all surfaces results in a cloud of debris, but my skimmer is not readily capable of dealing with the volume, especially in the larger form of snail poop and dead algae.
Water changes can be effective at removing debris, but I am hesitant to perform more than a small change each week. This is simply not enough turn over to remove all detritus from the tank. As such, I've decided to increase mechanical filtration.
The H.O.T. Magnum from Marineland is an interesting filter, specifically designed for powerful mechanical filtration in a temporary capacity. With standard filter pads, the detritus is trapped in the filter, and presumably broken down for bacteria to consume. I want to avoid a situation where mass amounts of organic material is broken down within the tank, as that would presumably create a rise in nitrates and dissolved matter, fueling algae growth.
The trick is to get this stuff out of the tank quickly. The Magnum filter includes a micron-sized filter core, surrounded by a larger filter pad. It is frequently used to polish the water of multiple aquariums, and is designed to be quickly and easily setup on the side of a tank for temporary filtration. My hope is that a daily ritual of scrubbing algae and basting the rock to suspend organic matter and waste, combined with this filter for quickly removing it, will get my tank back to a pristine state in a hurry.
The algae war in my reef tank continues. Despite some recent success, specifically in taming a rise in nitrates, the nuisance persists. Dosing AlgaeFix has greatly reduced forms of green algae on the rock and tank walls, but cyanobacteria continues to be an issue.
Cyanobacteria from my freswater planted tank
Also known as 'red slime', cyanobacteria is an obnoxious problem within the aquarium. It first appeared on the substrate, and not fully understanding how difficult it is to remove once it spreads, I was lazy on removing it fast enough. Scooping it off the substrate is simple, as it forms a tight mat that can be removed by hand. Once it spreads into the rocks and corals though, it starts to create strands that are extremely difficult to completely remove from the tank. Leftover pieces quickly spread across the tank mere days after cleaning.
While my water chemistry is good in regards to nitrates, a primary food source for algae and bacteria, the tank still has quite an issue with detritus build up. To rule this out as a possible source of energy for the cyano, I've decided to add some new snails to my tank. I'm hoping the combination and numbers that I've selected with be able to efficiently trim down new algae growth, while contributing to stirring up the sand bed and consuming waste and detritus.
6x Nassarius Snails (Nassarius sp.) An effective detritus consumer, that will hopefully remove quantities of uneaten organics from the rock and substrate.
6x Bumble Bee Snails (Engina sp.) Smaller in size, they can get into crevices within the rock, in addition to burying in the sand for food. Plus they look cool.
6x Turbo Snails (Turbo fluctuosa) An algae removing workhorse for the marine aquarium.
When I dealt with algae issues in my freshwater aquarium, the ultimate solution ended up being the addition of a dozen Amano shrimp, which quickly and efficiently removed all traces of nuisance algae from the tank within a few weeks. Looking for an equivalent silver bullet to deal with marine cyanobacteria has turned up mixed reports. Conventional wisdom states that nothing common to the aquarium trade will consume red slime. However, a few livestock dealers make the claim that scarlet hermit crabs, Paguristes cadenati, will eat it. Being in their commercial interest to market livestock as cures for common frustrations within the aquarium hobby, I remain skeptical.
As an experiment, and because Live Aquaria offers free shipping from Florida when you order $60 worth of 'clean up crew' animals, I am also bringing in 8 of these crabs. I'll monitor them carefully for any evidence of wether they eat this pest or not.
Tonight I tested some algae-specific parameters for the first time since changing my filtration strategy. The good news: nitrates dropped from 40ppm to 0. Phosphate remains at zero as always. Looks like the Seachem Purigen was a success.
The bad news is that I still have algae. After two weeks of doing the API Algaefix, I noticed it was growing back slower after a cleaning, and that some of the stringy algae was less green. Supposedly this is a sign of it working. I plan on continuing dosage for now. I'm hoping that by removing the nitrate, my corals will bounce back soon, and the algae will begin to disappear.
Another item of note, my clownfish have begun to display mating behavior. They've also been regularly digging a small pit in the gravel, which seems odd as I was under the impression that they generally prefer flat, solid surfaces for egg laying.
And finally, after a year of barely keeping SPS alive, I've been considering switching over to primarily soft corals. Live Aquaria has recently stocked up on some very interesting and colorful species, flying in the face of conventional wisdom that all soft corals are brown.
In light of my continued issues with nitrates (~40ppm) and the resulting algae, I've decided to make a few changes to the filtration mediums used in the filter. Up until now I've been running two bags of carbon along with some live rock rubble. Carbon is great for polishing the water, but it isn't actively helping with an accumulation of organics. The live rock has proven a good breeding ground for micro fauna (I regularly find abundant copepods and sponges), but there isn't enough volume to consider it an effective biological filter.
First, I reintroduced the zeolite media I had experimented with last summer. The highly porous nature of zeolite absorbs impurities and serves as a breeding ground for beneficial bacteria that reduce organics. I started low with the volume of zeolite, and hope to increase it based on how the corals react.
Secondly, I added 100ml of Seachem Purigen. This is a porous chemical filtration medium that works as a sponge for organic matter in the water. By removing this material from the water column, it never has a chance to complete the nitrogen cycle and become nitrate. Thanks to the abundant volume of the Aquaclear filter, I am also able to continue running a bag of carbon and the live rock rubble.
The last change to my maintenance routine is a little more controversial, at least in my mind. I am generally very conservative about introducing any form of additives, and especially opposed to chemical treatment of algae. That said, after reading a long thread about the effectiveness of API's Algaefix, I had to try it. The experiences of many aquarists confirmed the claim that this product will not harm anything within the tank, from fish to invertebrates, but will eliminate most forms of algae within weeks. An $8 bottled solution is very tempting after spending a few months scraping algae and performing multiple water changes each week.
The current dosing schedule is 3ml of Algaefix every three days, to be reduced when algae shows signs of dying off. I will update with progress.
Crazy idea of the day: adding a whole lot of macro algae to my tank, making it a "planted" reef.
• Motivator 1: I miss having a planted tank. • Motivator 2: Algae would make the tank more diverse. • Motivator 3: Having a unique tank look. • Motivator 4: Potentially would take up some nutrients.
The real thought process trigger was this recent post on the Glass Box, with a video of a Japanese tank. The sand bed is planted with turtle grass,
Thalassia testudinum.
I also like the look of Halodule beaudettei, which is more like freshwater hairgrass. Combined with turtle grass, you can get an interesting meadow effect, an often sought after look for freshwater planted tanks. If I could get this to grow thick enough, it would be a really interesting effect with the live rock rising out of it.
Live Aquaria has a good selection of marine algae, but they are often out of stock. I found a small company, Gulf Coast Ecosystems, that specializes in tropical algae collection and aquaculture. I'm going to do some more research right now, but think this may be an interesting change for the tank. The only (major) downside I can think of is that these plants are native to the Caribbean, and the majority of my stock is from the South Pacific. Though I've never intended to create a strict biotope, it would be more of an unusual species mix than I've generally preferred to make.
Over the preceding two months I've noticed the nitrate levels in my reef tank creeping up from unmeasurable to 20ppm. I blame this squarely on a Glassbox post about fish being fed enough; worried that I was compelling my fish to be "coralexic", my tank has since become an all you can eat Chinese buffet. I believe the elevated nitrate level is responsible for some of my corals browning out. Also I've noticed a few strands of dreaded hair algae appearing within the tank, as well as increased diatoms on the glass of the tank.
My plan is to keep up with my weekly 5% water changes, and also to introduce a new form of nutrient export. If anyone has advice on the choices below, please volunteer your expertise in the comments. Also if you'd like to sign up to come over and do some of the water changes, please feel free.
Option 1: Convert Aquaclear filter into an algae scrubber
Originally I bought this filter with intent of modifying it into a refugium, filled with live rock rubble and chaeto. Since, I've been running a small amount of rubble and two bags of carbon. This option would involve adding a small light above the filter, installing a grate over the exit, and filling the filter with chaeto algae to remove nitrates.
Pros: cheap, fun project with existing equipment Cons: reduced volume of carbon, not enough volume for a useful quantity of algae
Option 2: Hang-on refugium
Although a real sump is out of the question for this tank, there are out of the box options for hang on refugiums. This would perform roughly the same function as a modified Aquaclear filter, but with a lot more volume. These things always struck me as somewhat gimmicky though. I would run mostly chaeto within the refuge, along with some sort of sand bed and live rock rubble.
Pros: More volume, greater biodiversity, out of the box solution Cons: Expensive, unsure of their effectiveness, possibility of flooding?
Option 3: Another solution? Larger skimmer to cut the problem off at the source? Less feeding? Better sand bed maintenance? Some sort of addition clean up crew? All of the above? Let me know what you think.
After the nine thousandth call from the New England Aquarium informing me that my membership was about to / had expired, I figured I might as well march over there and renew it. They have a good sized coral tank, and I was looking for some photos I could use for raw material while working on the design of this blog.
It was interesting to observe the tank now, after five months of research into setting up my own tank. Previously it had been fairly inspirational, but now I was able to identify some short comings, or at least what would be viewed as such by the reef tank elite. Bubble and hair algae was rampant throughtout the tank, and the fish and invertebrate diversity was relatively low for what would be possible in a tank of that size. That said, it is still a beautiful aquarium and only one of the many tanks worth spending some time with at that facility.
Click any of these photos to head over to Flickr where you can get a larger view of them.
Photo Credit: Prof. Gordon T. Taylor, Stony Brook University, USA
Last night I noticed a golden-brown colored dust growing on the substrate and rocks. I spent some time searching for algae species identification charts, and eventually came across an About.com article regarding diatoms. A trip to Wikipedia and some other resources confirmed that was what I had most likely observed in my tank. Of particular interest to me was this section from About:
This type of algae outbreak typically occurs when a tank is just completing or has finished the nitrogen cycling process, new live rock is introduced, as the curing process can add nutrients when some organisms on the rock dies off, or tank maintenance has been neglected.
Obviously that would pertain to current events in my reef tank. I had assumed that ammonia levels, which had been as high as 8ppm three days earlier, would require at least another week to subside, and had resolved not to waste my time and test kits checking it every day. The growth of diatoms and subsequent information about them forced a change of mind, and I conducted my usual tests this evening with surprising results: ammonia had indeed dropped to somewhere between 0.25 and 0ppm, an impressive down swing from the levels recorded on Sunday. Nitrite and Nitrate were still high, but that would be expected as they are the products of processed ammonia.
Also of interest was this summary of diatoms and their use of silicates, found in the Wikipedia article:
Diatoms cells are contained within a unique silicate (silicic acid) cell wall comprised of two separate valves (or shells). The biogenic silica that the cell wall is composed of is synthesised intracellularly by the polymerisation of silicic acid monomers. This material is then extruded to the cell exterior and added to the wall. Diatom cell walls are also called frustules or tests, and their two valves typically overlap one other like the two halves of a petri dish. In most species, when a diatom divides to produce two daughter cells, each cell keeps one of the two valves and grows a smaller valve within it. As a result, after each division cycle the average size of diatom cells in the population gets smaller. Once such cells reach a certain minimum size, rather than simply divide vegetatively, they reverse this decline by forming an auxospore. This expands in size to give rise to a much larger cell, which then returns to size-diminishing divisions. Auxospore production is almost always linked to meiosis and sexual reproduction.
Once again, an insightful article from Randy Holmes-Farley helps to clarify both the cause and effect. As mentioned above, diatoms construct their cell wall from silicate, hence their presence could be considered an indicator of silicates being present in the aquarium. His article discusses how silica occurs in the ocean and in the aquarium, as well as what organisms use it and how it can be controlled and dosed. Great stuff.
My assumption is that there would be a high level of silicates found in my tank due to a number of recent inputs: • Unfiltered tap water for the initial tank fill • Sand and sediment on the live rock • Live sand substrate
So there should be plenty of raw material for diatoms, in addition to the high levels of light for photosynthesis (I've been running the tank lights 8 hours a day) and nitrate for fertilizer. Conventional wisdom seems to indicate that after the initial outbreak of diatoms in a new aquarium one can expect green algae to replace it. My initial hobbyist panic response to seeing my pristine new white sand bed polluted with some form of new algae has since been replaced with curiosity now that I've learned about the circumstances under which it appears. I intend to see if I can get a sample out of the tank and take a look under the microscope this evening, as the imagery on Wikipedia is quite stunning.
* The color of the ammonia test was actually somewhere between 0.25ppm and 0ppm, and closer to 0. In the interest of caution I am rounding up on the chart.
