- Location
- Overland Park, KS
So this chapter can be summed up as follows: Algae Happens.
What to do? We can do our best to create the conditions so that beneficial Macroalgae thrive, and at the same time, limit the sometimes detrimental or at the very least, nusiance algae growth.
Fenner focuses not on wiping out all algae in the tank, but rather, on preventing and controlling only the types of algae that are undesirable. He reminds us that algae is a fantastic bioindicator of the health of our tank - if water quality has so declined that the algae is dying off, you know you've got a problem!
A convincing argument for having algae in our systems other than use as bioindicator is that it is a natural system for nutrient removal. Many animals eat algae.
There are two major classes of algae, microalgae (the filmy and slimy guk we hate) and macroalgae (which Fenner labels "purposly grown," though I would hardly say I purposfully grow bubble algae...)
Algae are oxygen-producing unicellular autotrophs (self-feeders) that reproduce asexually. They lack specialized structures such as roots, stems or leaves. Taxonomic classification is based upon color:
Blue-green algae ("bad") is closely related to bacteria. This algae is a good indicator that things are not well in our system. They grow best in underaerated, stagnant, overfertilized waters.
Green Algae: what we are most familiar with, occurring in many forms - floating, attached, swimming and seasonal surface blooms... (quoted, p. 134)
Brown and Red Algae: mostly marine algae, including coralline algae and kelp.
Diatoms and Dinoflagellates: single-celled, microscopic, often thought of as nuisance, but beneficial in terms of O2 production, "eating" nutrients, and thus outcompeting for other (worse) algal forms. Not pretty (the brownish scum on our sand beds/glass...), but not bad for the water or the tank, except for Amyloodinium (formerly Oodinium), an infectious disease! Zooxanthellae are dinoflagellates for the most part, living symbiotically within the tissue of many corals and Tridacna clams.
Fenner reminds us again that many algal types are beneficial and desirable in our tank, and tells us that by limiting the light, limiting nutrients (don't overfeed!!!) and introducing "biological controls" (animals that EAT algae), we can keep algae in our tanks under control. Most algal forms thrive in stagnant water, so good circulation will limit many nusiance algaes.
How to limit growth of the nusiance algae and encourage growth of the desirable algae:
Lighting: "more intense lighting over longer photoperiods favors macroalgae over micro," but not always (not so helpful there...) - so for us reefers, Fenner points out that keeping algae munchers (snails, crabs, tangs, blennies) in our tanks is pretty much a must, since our corals rely on the light during a long enough photoperiod to support THEIR algae (zooxanthellae), but we don't want much algae outside of the corals!!!
Temperature: Most algae forms we want thrive in the mid 70's. Most of the ones we don't want like higher temps (or respond well to fluctuations in temp)
Filtration: Activated Carbons and Poly Filters may prevent microalgal blooms. Fenner does not believe that nitrate and phosphate removers are usefull in limiting nutrient availability. On the other hand, a healthy bacterial culture in your filter system will successfully remove nutrients from the water. Best by far, though, is the protein skimmer (foam fractionator, actually...)
Macroalgae: Growth of this algae will itself discourage growth of nusiance algae, as it will outcompete the microalgal forms for nutrients as well as light. Corallines in particluar are great, as (not only are they beautiful in our systems, but also) they produce chemicals that inhibit microalgae growth!
Pollutants: WEAR GLOVES when putting our hands into our systems, as we introduce all kinds of gunk when we put our hands in the water (including food!) Extra food counts as pollutants. Frequent, partial water changes are critical to decreasing pollutants in the water.
Biological Controls: animals we can and do add... Turbo, Astraea snails, blennie species, tang species, herbivorous hermit crabs...
Mechanical Controls: scrape the inside of the tank glass, clean up decor from slime when needed... (WEAR GLOVES....)
Chemical Controls: LEAST DESIRABLE choice of all!!! Avoid antibiotics (anti = against, biotic = life == you can kill your system!!!) Copper = toxic to all life, particularly non-fish life in our systems!!! If you must use a chemical control, Fenner says, watch out for toxic side effects, and do water changes if you see any!!!
(Please forgive me - this is getting quite long. I hope I'm not going overboard, but I fear maybe I am?....)
Fenner sums up this section by saying, leave well enough alone - some algae is a good thing - a sign of a healthy system. If you do develop a problem, be sure to find the root of the algal bloom - don't just wipe out the algae, correct the condition that allowed it to happen!
Growing Macroalgae Benefits include:
biofiltering -- improving water quality by removing nitrates, buffering pH, taking in CO2, producing O2, helping to balance trace elements (magnesium, phosphate, iron)
nusiance algae control, serving as food for many marine fish and inverts, shelter and ornamentation
To keep macroalgae, we need:
1. a cycled tank
2. adequate nutrient levels (don't add more stuff for their up-keep - what we feed our fish is usually enough!)
3. enough light
4. no livestock that will wipe out the macroalgae we wish to keep
5. moderate water flow
Types of macroalgae we might select:
genus Caulerpa is most popular and successful in the swf trade. They often grow so well that they must be trimmed back to keep from taking over. There are about 70 species of Caulerpa available.
Penicillus sp. - Marman's Shaving Brush
Halimeda sp. - hard to chew, so good for if you have algal grazers but want "plant life" in your tank...
Udotea sp. - looks like a soft green fan
Fenner closes with this bit of advice -- "A properly maintained marine aquarium will always have the predisposing conditions to grow algae. given that reality, why not grow some that you prefer?" (p. 139)
...sounds like good advice to me!
What to do? We can do our best to create the conditions so that beneficial Macroalgae thrive, and at the same time, limit the sometimes detrimental or at the very least, nusiance algae growth.
Fenner focuses not on wiping out all algae in the tank, but rather, on preventing and controlling only the types of algae that are undesirable. He reminds us that algae is a fantastic bioindicator of the health of our tank - if water quality has so declined that the algae is dying off, you know you've got a problem!
A convincing argument for having algae in our systems other than use as bioindicator is that it is a natural system for nutrient removal. Many animals eat algae.
There are two major classes of algae, microalgae (the filmy and slimy guk we hate) and macroalgae (which Fenner labels "purposly grown," though I would hardly say I purposfully grow bubble algae...)
Algae are oxygen-producing unicellular autotrophs (self-feeders) that reproduce asexually. They lack specialized structures such as roots, stems or leaves. Taxonomic classification is based upon color:
Blue-green algae ("bad") is closely related to bacteria. This algae is a good indicator that things are not well in our system. They grow best in underaerated, stagnant, overfertilized waters.
Green Algae: what we are most familiar with, occurring in many forms - floating, attached, swimming and seasonal surface blooms... (quoted, p. 134)
Brown and Red Algae: mostly marine algae, including coralline algae and kelp.
Diatoms and Dinoflagellates: single-celled, microscopic, often thought of as nuisance, but beneficial in terms of O2 production, "eating" nutrients, and thus outcompeting for other (worse) algal forms. Not pretty (the brownish scum on our sand beds/glass...), but not bad for the water or the tank, except for Amyloodinium (formerly Oodinium), an infectious disease! Zooxanthellae are dinoflagellates for the most part, living symbiotically within the tissue of many corals and Tridacna clams.
Fenner reminds us again that many algal types are beneficial and desirable in our tank, and tells us that by limiting the light, limiting nutrients (don't overfeed!!!) and introducing "biological controls" (animals that EAT algae), we can keep algae in our tanks under control. Most algal forms thrive in stagnant water, so good circulation will limit many nusiance algaes.
How to limit growth of the nusiance algae and encourage growth of the desirable algae:
Lighting: "more intense lighting over longer photoperiods favors macroalgae over micro," but not always (not so helpful there...) - so for us reefers, Fenner points out that keeping algae munchers (snails, crabs, tangs, blennies) in our tanks is pretty much a must, since our corals rely on the light during a long enough photoperiod to support THEIR algae (zooxanthellae), but we don't want much algae outside of the corals!!!
Temperature: Most algae forms we want thrive in the mid 70's. Most of the ones we don't want like higher temps (or respond well to fluctuations in temp)
Filtration: Activated Carbons and Poly Filters may prevent microalgal blooms. Fenner does not believe that nitrate and phosphate removers are usefull in limiting nutrient availability. On the other hand, a healthy bacterial culture in your filter system will successfully remove nutrients from the water. Best by far, though, is the protein skimmer (foam fractionator, actually...)
Macroalgae: Growth of this algae will itself discourage growth of nusiance algae, as it will outcompete the microalgal forms for nutrients as well as light. Corallines in particluar are great, as (not only are they beautiful in our systems, but also) they produce chemicals that inhibit microalgae growth!
Pollutants: WEAR GLOVES when putting our hands into our systems, as we introduce all kinds of gunk when we put our hands in the water (including food!) Extra food counts as pollutants. Frequent, partial water changes are critical to decreasing pollutants in the water.
Biological Controls: animals we can and do add... Turbo, Astraea snails, blennie species, tang species, herbivorous hermit crabs...
Mechanical Controls: scrape the inside of the tank glass, clean up decor from slime when needed... (WEAR GLOVES....)
Chemical Controls: LEAST DESIRABLE choice of all!!! Avoid antibiotics (anti = against, biotic = life == you can kill your system!!!) Copper = toxic to all life, particularly non-fish life in our systems!!! If you must use a chemical control, Fenner says, watch out for toxic side effects, and do water changes if you see any!!!
(Please forgive me - this is getting quite long. I hope I'm not going overboard, but I fear maybe I am?....)
Fenner sums up this section by saying, leave well enough alone - some algae is a good thing - a sign of a healthy system. If you do develop a problem, be sure to find the root of the algal bloom - don't just wipe out the algae, correct the condition that allowed it to happen!
Growing Macroalgae Benefits include:
biofiltering -- improving water quality by removing nitrates, buffering pH, taking in CO2, producing O2, helping to balance trace elements (magnesium, phosphate, iron)
nusiance algae control, serving as food for many marine fish and inverts, shelter and ornamentation
To keep macroalgae, we need:
1. a cycled tank
2. adequate nutrient levels (don't add more stuff for their up-keep - what we feed our fish is usually enough!)
3. enough light
4. no livestock that will wipe out the macroalgae we wish to keep
5. moderate water flow
Types of macroalgae we might select:
genus Caulerpa is most popular and successful in the swf trade. They often grow so well that they must be trimmed back to keep from taking over. There are about 70 species of Caulerpa available.
Penicillus sp. - Marman's Shaving Brush
Halimeda sp. - hard to chew, so good for if you have algal grazers but want "plant life" in your tank...
Udotea sp. - looks like a soft green fan
Fenner closes with this bit of advice -- "A properly maintained marine aquarium will always have the predisposing conditions to grow algae. given that reality, why not grow some that you prefer?" (p. 139)
...sounds like good advice to me!
