[chrisfrat]

Well, I have a problem with your idea here. It's a great idea in theory, but the macro and SPS need dramatically different nutrient levels. The macro will die if there is not an ample amount of nutrients in the water, and the SPS won't do so well if there is that much nutrients in the water. So, IMO, the two shouldn't go together. If you want it heavily stocked with SPS, it probably should have a skimmer. If you want it heavily stocked with macro, it shouldn't have a skimmer.

 

[chrisfrat]

With LPS, it would be a little better, but since they live naturally on open reefs, they require fairly low nutrient levels. Macro algae, since they naturally live in lagoons etc, they require higher nutrient levels. Personally, I would never keep Macro in my tank because if its growing, it means you have high nutrient levels. What are your reasons for wanting macro?

 

[chrisfrat]

Macro can be good-looking in the DT, but you really should be trimming it constantly. It is not good filtration because they are constantly both binding and releasing nutrients, so unless you physically remove them, they aren't doing much.

 

[chrisfrat]

I would never use macro, but some people do successfully. I'd much rather clean out a skimmer. In my opinion, you shouldn't run a tank over 25 or so gallons without a skimmer.

 

[chrisfrat]

Does algae grow in the wild? Yes. In places where there is high enough nutrient levels. The kind of macroalgae you are looking at adding to your tank is usually found in intercoastal, lagoonish areas where there is low flow and low nutrient exchange. The algaes you find while snorkeling aren't necessarily the same kind that you would want in a fuge or for nutrient control. Algae won't grow without a fuel source. If a pond is getting polluted, we frequently see cyanobacteria outbreaks. In closed systems where there is little nutrient exchange, like a pond or our tanks, the cyano simply overtakes other species. It produces a lot of O2, raising pH because a lot of H ions = high pH. The animals die from shock due to pH changes, decompose, providing algae with more nutrients, and the cycle repeats. That was a bit of a tangent but I feel it was relevant. Read the section on pH at this link. IMO, the biggest argument against using macro is that it doesn't really bind nutrients, as it does release nutrients back into the water.

 

[chrisfrat]

The idea isn't that there being algae in the system is bad. The idea is that it is bad that there is enough nutrients in the system to grow algae.

 

[chrisfrat]

The idea of algae using up phosphates is also a bit misleading. Algae only takes in as much phosphate as it needs to operate at the level of the surrounding nutrients. Now what does it do with phosphates? Well the phosphates are converted to ATP (energy) and the ATP is spent and burned. The Phosphate is not destroyed or becomes part of the cells afterward, Spent ATP turns to ADP. ADP is then recycled back to ATP via photosynthesis. The phosphate is not lost its constantly reused. So the need for more phosphates is not required once its at operating levels which is determined by surrounding environment levels. As its not a consumed and stored resource its levels are static due to it being just recycled.

I feel like an appropriate sidebar here would be the law of conservation of matter (and energy). These laws simply state that neither matter nor energy is created or destroyed. It only moves into and out of systems. This applies to Invic's argument with ATP (adenosine triphosphate) and ADP (adenosine diphosphate). The third P is added back in the light reactions of photosynthesis. In the human body, each ATP molecule is recycled 500 to 750 times every day. Since ATP cannot be stored, it is used very quickly after it is synthesized.

What I'm saying is, the P just keeps getting reused and can only be actually removed from the system by you.

 

[chrisfrat]

High pH is in fact *lack* of H ions.

The pH is equal to -log10 c, where c is the hydrogen ion concentration in moles per liter.

My bad, got that one backwards.

 

[chrisfrat]

Future and Floyd, thank you and I get the analogy but I think the base point missing is that if the carrots are phosphates then the farm/soil must be our rock or sand right? So, even if the rabbits eat the carrots and the foxes eat the rabbits, in our tanks you are saying the carrots still increase because they populate quicker than the mammals. If that's right, then once in a while I can go in with my tractor and dig out a bunch of soil and replace it with fresh soil - or sand in the case of a tank? If that's right then doesn't this increase the argument for having sand and plants (algae) as natural agents and then managing their upkeep?

I'm a big fan of aquaponics and though I know fresh and salt water are very different beasts, doesn't it remain a case of finding the right balance? In aquaponics you need the right amount of fish to produce enough waste to feed the vegetables that in turn produce nutrients to feed the fish. Get the right balance and you remove fish as they breed and vegetables as they grow.

If this all sounds nuts feel free to shout NO!!!!!, I'm just trying to apply other logic to this.

Thanks guys
Adam

That would make sense, right? But in the case of our tanks, everything poops carrots too, no matter how many are eaten. Also, nothing really "eats" the carrots. They are only removed by WCs, skimming, or (for the sake of this discussion) macro algae. Macro algae would be the closest comparison to your rabbits, but once again, the rabbits also poop carrots. The macro has a give/take relationship with the water column. It isn't all intake.