Bolus dosing

[areefer01]

I agree with this to a point. The high phosphate/ high coral load tanks that don’t suffer algae problems likely limit other necessary elements required for rampant algae growth or have other methods of control such as allelopathy.

Proper balance, and type, of herbivores.

 

[Koleswrath]

Proper balance, and type, of herbivores.

This as well yes. Little harder in smaller tanks.

 

[Hans-Werner]

Is it definitively possible that these deposits can be locally dissolved by bacteria and thus become available for algae, for example?

It is proven for mangroves and phosphate solubilizing microbes. The mangroves excrete organic carbon through the roots which bacteria use to dissolve phosphate and make it available to the mangrove roots. I think algae can act in a similar way, especially Caulerpa with its runners and rhizoids. Valonia at the contact with substrate also forms rhizoids.

Algae under nutrient deficiency excrete organic carbon because the photosynthesis is still working but they can't make full use of the produced organic carbon under nutrient deficiency. So they simply excrete organic carbon.

I am not sure whether the brown precipitate is really organic or maybe iron and manganese (co-)precipitated with calcium carbonate and phosphate. This may also help the Valonia to thrive on the precipitates caused by kalkwasser since the metals may also get dissolved by organics and bacteria.

 

[Hans-Werner]

I’m just not convinced that phosphate from rock drives a lot of algae problems since many tanks with elevated phosphate everywhere do not have algae problems.

Here the metals may play a role. With phosphate in the water also corals have access to phosphate and their growth may deplete the water in iron, manganese and maybe other essential trace metals. With phosphate and metals precipitated by kalkwasser corals would be excluded and algae may make use of the precipitated micro and macro nutrients.

Both, in reefs and in tanks, freshly exposed coral skeletons are rapidly overgrown by algae and cyanobacteria because the skeletons are full of precipitated nutrients, the nutrients the corals depleted from the water.

 

[Garf]

Here the metals may play a role. With phosphate in the water also corals have access to phosphate and their growth may deplete the water in iron, manganese and maybe other essential trace metals. With phosphate and metals precipitated by kalkwasser corals would be excluded and algae may make use of the precipitated micro and macro nutrients.

Both, in reefs and in tanks, freshly exposed coral skeletons are rapidly overgrown by algae and cyanobacteria because the skeletons are full of precipitated nutrients, the nutrients the corals depleted from the water.

However, algae also grows great on plastic mesh screens, where there's no precipitated advantage, that I'm aware of. Just space availability, light, flow, lack of herbivory and an attachment site. I'm failing to see the relevance of this advantage if folk are maintaining detectable nutrients in bulk water for coral health reasons.

 

[Hans-Werner]

However, algae also grows great on plastic mesh screens, where there's no precipitated advantage, that I'm aware of. Just space availability, light, flow, lack of herbivory and an attachment site. I'm failing to see the relevance of this advantage if folk are maintaining detectable nutrients in bulk water for coral health reasons.

This is only true if the plastic mesh screen is new. Since plastics are more or less hydrophobic, bacteria will settle and grow rapidly and precipitate metals for example.

Nutrients will limit either coral growth or algal growth. One or several nutrients will always be growth limiting. If corals get enough phosphate they have the potential to deplete nitrogen and trace metals in a way that is limiting algal growth. If I precipitate phosphate and metals, corals will be limited by phosphate and maybe trace metals while algae potentially have access to the precipitated nutrients by the mechanisms explained above. Also corals are loosing their potential to deplete nitrogen and trace metals when limited by phosphate.

It are not always simple direct effects, effects may be indirect.

 

[MnFish1]

I recently (caring for a neighbors koi) in a 72 gallon bow front (obviously freshwater ) - but it bring up a question - After the last death - I just left the light schedule the same - 12hr/day - no feeding, - Nothing grew - no algae, etc. I was stupid for not measuring the nutrients - however - there is a theory out there that enough nutrients from the environment fall in to the tank, etc - to allow algae growth - The glass is still clear and everything looks fine in the tank (except its empty). The cause - my friend overfilled the tank up to the cover (which covers part of the tank) - and the koi were too big for overwintering in such a small tank. In any case - The more I do - the less some of the conventional wisdom seems to make sense

for @brandon429 - the tank is left running over the summer when the fish are outside - I then just drop them in - and these 7 (ii know too many) koi were fine for 2 months - so though not tested - I don't think ammonia was the issue - but its more evidence - that nitrifying bacteria can remain dormant for periods of time

 

[Randy Holmes-Farley]

Both, in reefs and in tanks, freshly exposed coral skeletons are rapidly overgrown by algae and cyanobacteria because the skeletons are full of precipitated nutrients, the nutrients the corals depleted from the water.

That’s certainly a plausible reason. But glass also grows algae well without such binding.

 

[MnFish1]

That’s certainly a plausible reason. But glass also grows algae well without such binding.

IMHO - With the right nutrients in the water - anything will grow on any empty space

 

[Garf]

IMHO - With the right nutrients in the water - anything will grow on any empty space

Dead coral skeleton latice also provides a porous structure seemingly ideal for algal recruitment. Back in my algae scrubber investigations long ago, cement had the ideal porosity for GHA recruitment for example. I'm not sure how this can be disregarded when it complies with both the space and attachment site criteria I listed previously.

 

[MnFish1]

Dead coral skeleton latice also provides a porous structure seemingly ideal for algal recruitment. Back in my algae scrubber investigations long ago, cement had the ideal porosity for GHA recruitment for example. I'm not sure how this can be disregarded when it complies with both the space and attachment site criteria I listed previously.

I dont know if you're talking about my freshwater example - but - I was actually amazed as well - as my thesis has always been 'the uglies are not caused by chemicals as much as they are caused by empty space' (of course the things that would fill the empty space would also remove potential nutrients )

 

[SDchris]

Here the metals may play a role. With phosphate in the water also corals have access to phosphate and their growth may deplete the water in iron, manganese and maybe other essential trace metals.

I would agree with that.
Two years ago my BB tank had a bad bubble algae outbreak, at the time I was to busy to deal with it so let the tank go. The few coral died out. The few fish that were in the tank were still feed every day with a fresh seafood mix. No water changes and skimmer rarely emptied.
5 - 6 months later the rock and glass became extremely clean, with only a few bubble algae the only thing remaining. Yet PO4 and NO3 were reasonably elevated.
My assumption, as you pointed out above, was the lack of algae was due to a depletion of one or more other elements.
Yet, the biological filtration was still stable, as evident by a lack of ammonia, (tested a couple times), and general appearance of of fish and snails.

Before reseting the tank, I wanted to test a theory on: rock oxygen levels, boundary layer thickness and nutrient availability, as being drivers in algae growth.
Tied a small plastic bag around the end of some branch rock. Left it for 48hrs and then removed it. Three days later a patch of cyano formed.

 

[Hans-Werner]

Back in my algae scrubber investigations long ago, cement had the ideal porosity for GHA recruitment for example. I'm not sure how this can be disregarded when it complies with both the space and attachment site criteria I listed previously.

You are doing the judgement one-sided without considering all (i. e. the chemical) aspects. Cement is full of "stuff" like iron, aluminium, silicate etc.. I doubt that a properly made cement has much porositiy except you add additives that make it porous. Even when adding porous minerals like pumice, zeolithe, perlite or coral sand the pores are closed.

 

[Hans-Werner]

That’s certainly a plausible reason. But glass also grows algae well without such binding.

Yes, but this is again approaching the matter from the wrong side. If algae have the perfect nutrient conditions they will grow anywhere. I think the question is rather, why don't they do it in most tanks. Under real-world conditions somewhen some nutrient will get limiting, for algae most likely iron. This would be in good agreement with the "high nitrate systems" and "high nitrate theories".

I think in established and well-running reef tanks herbivory is rather overestimated. Most "algivore" fishes are in fact detrivore and maybe rather deprive the algae from nutrients from the detritus. The snail population usually drops to a low level after the initial phase. In established reef tanks most fish and also hermit crabs may feed more on the fish food dropped into the tank than on algae. So, what really stops algal growth?

 

[Garf]

You are doing the judgement one-sided without considering all (i. e. the chemical) aspects. Cement is full of "stuff" like iron, aluminium, silicate etc.. I doubt that a properly made cement has much porositiy except you add additives that make it porous. Even when adding porous minerals like pumice, zeolithe, perlite or coral sand the pores are closed.

Ok, perhaps I'm remembering things wrong but I'm under the impression that organisms like hair algae have no internal circulatory system and rely on local diffusion from the bulk water to get nutrients. They are merely single cells glued together, evidenced by doubling times on algal scrubber screens. If this is still the case, algae not in direct contact with the substrate would not necessarily benefit from the precipitation mechanism, yet algae can get rather long, certainly longer than explained by the precipitation theory.

 

[Hans-Werner]

Ok, perhaps I'm remembering things wrong but I'm under the impression that organisms like hair algae have no internal circulatory system and rely on local diffusion from the bulk water to get nutrients. They are merely single cells glued together, evidenced by doubling times on algal scrubber screens. If this is still the case, algae not in direct contact with the substrate would not necessarily benefit from the precipitation mechanism, yet algae can get rather long, certainly longer than explained by the precipitation theory.

Most of "our" algae like Caulerpa and the Cladophorales (Chaetomorpha, Valonia etc.) are siphonous green algae. This means their thalli consist of huge single cells (in Chaetomorpha you can see chains of huge cells). At least Caulerpa also has a circulatory system: "Caulerpa species support their large cell size by having the cytoplasm circulate constantly, supported by a network of microtubules. This behavior was known in 1967.[10]"

In Cladophorales usually a thin layer of cytoplasm surrounds a hughe vaculoe in which nutrients are circulating freely. In the liquid filled bubbles of Valonia the cytoplasm is in the thin green layer and the liquid filled inner is the vacuole. I found extremely high concentrations of nitrate in Valonia vacuoles.

 

[areefer01]

I think in established and well-running reef tanks herbivory is rather overestimated. Most "algivore" fishes are in fact detrivore and maybe rather deprive the algae from nutrients from the detritus. The snail population usually drops to a low level after the initial phase. In established reef tanks most fish and also hermit crabs may feed more on the fish food dropped into the tank than on algae. So, what really stops algal growth?

This is the part I do not get. Maybe understand is more proper. I feel that those of us with higher nutrient systems and no algae issues is because we have a balanced herbivore population. To me this includes fish, snails, hermits, and reef hardscape.

I see the growth on the glass panes but do not see anything on the reef structure. I clean the glass and my fish eat the algae. I see snail trails on the glass if I ignore it. I see astrea stars on the rocks along with mini stars and strombus snails. In my case high nutrients is 24 - 34 ppm nitrate and .70 to .80 ppm phosphate. I've kept my phosphate as high as 1.7 ppm.

I have nothing to prove this of course but this is how my system works and what I believe. I haven't delt with algae issues in a high nutrient system and I feel it is due to herbivories being in balance and right types. My reef is a couple months past 8 years now.

Hope your day is well.

 

[MnFish1]

This is the part I do not get. Maybe understand is more proper. I feel that those of us with higher nutrient systems and no algae issues is because we have a balanced herbivore population. To me this includes fish, snails, hermits, and reef hardscape.

I see the growth on the glass panes but do not see anything on the reef structure. I clean the glass and my fish eat the algae. I see snail trails on the glass if I ignore it. I see astrea stars on the rocks along with mini stars and strombus snails. In my case high nutrients is 24 - 34 ppm nitrate and .70 to .80 ppm phosphate. I've kept my phosphate as high as 1.7 ppm.

I have nothing to prove this of course but this is how my system works and what I believe. I haven't delt with algae issues in a high nutrient system and I feel it is due to herbivories being in balance and right types. My reef is a couple months past 8 years now.

Hope your day is well.

I agree - and it's the reason that I think all of the talk about Redfield ratios, nitrate and PO4 levels does not seem to correlate with algae growth in tanks. especially the Redfield ratio (to me) makes no sense. What I mean by this is many ultra low nutrient systems do quite well - and many high nutrient tanks do as well.

0 nitrate and 0 phosphate does not mean there is none in the tank - it means that the tank is in steady state - where all of the N and P being added (with food, etc) is being used up by 'something' In a tank full of coral its probably being used by coral in a tank with bare rock its going ro result in algae formation. As others have also said there are other limiting factors iron, etc - that are hard to reliably measure.

IMHO - the uglies (which are not automatic) happen when someone gets a new tank - puts in rock - dry or live - but less issues with live (ocean live). put in some fish and wonder why algae starts growing.

 

[Oldreefer44]

Reefbum has a new progress report on his Bolus dosing

 

[areefer01]

Reefbum has a new progress report on his Bolus dosing

One noteworthy comment he made. He is adding 800 ml alkalinity (or almost he said) per bolus dose. RHF always says it comes down to math. 800 x 7 days in the week = 5,600 ml of alkalinity per week. Rounding up that is 1.5 gallons of alkalinity per week. That is expensive if one uses named brands.

While he does have a SPS dominated system it isn't a large one. It isn't small either but it isn't overly large.