Well, you actually know how I felt back about 10 years ago when I suggested folks add PO4 to planted tanks. Steve had the classic lean tank that was suppose to do everything right, then saw my tank and rethought everything.
He dosed PO4 and the rest was history.

I got very little support

But it's like this: lead by example.
I have many tanks I take care of that have been using EI for years and in a couple of cases, decades.

I mentioned adding ferts to Macro group on Reef Central and it blew a few mines, but they were very receptive to the notion, but they like Macros also......

Perhaps the aquarist there are unaware of how a plant/macro algae grows?
They are in general, critter folks, not plant folks.

Some points to ponder with them:
You cannot have two limituing nutrients at the same time.
If you limit PO4, NO3/NH4 uptake suffers
If you limit NO3, PO4 uptake will suffer.
If the algae is limited by PO4, so will the much larger and higher demand macro algae.

Ask them why their Caulpera melts and goes sexual.
Most have no clue.
Try limiting the NO3 and measuring it carefully.
You see a correlation between low/absent NO3 and melting.
Sexual stages are often for harsh times so that the alga can make it through in a resistant form till the environment is good again.

No N sources, the algae goes sexual.
If you add NO3 and maintain 5-10ppm of NO3 via KNO3 dosing, the alga will not melt nor ever go sexual.

Adding PO4 is sometimes required, but not always.
Depends on the loading rate of the tank.

If the macro biomass and the critter biomass are scaled up together, then you can strike a nice balance with little supplementation.

But if the tank is going along fine and the Chaeto or Caulerpa increase 2-3x in biomass, clearly they are going demand more nutrients as the biomass increases, so if you maintain good stable biomass and export the trimmings, then things are fine.

If you let things go and the biomass grows wildly, then the macros will strip most everything out of the water column and then die back, causing a crash.

Macros are not like FW plants though.....the systems are different, but there are some similarities.

PO4 dosing can help in some tanks, as can Fe and KNO3.
Most tend to test a lot.

Few reef folks experiment, they are too scared everything will die.
They do test to measure their parameters, but not to experiment.
Macro algae grows much faster and is no big deal if it dies back, so it makes better model at understanding the Marine systems and dynamics with uptake.

Still, refuges are great, but oddly few do their tank's scaping with them, and they are every bit as nice as the corals and offer a lot of added benefits.

Sarah took to the macro dosing well, as have several other folks.
Their observations as well as my own have opened up the field and potential for better horticulture.

But in terms of a skimmer vs a refuge, they have to know how to grow a plant before they can manage them effectively for their system.
It's like not knowing how a skimmer works and setting it up all wrong.

The deal is that the proof is in the practical results for most folks.
No skimmate with a refuge that's well run.
Lower NH4. More reduce carbon for the bacteria to help cycling, better nutrient ranges for the microalgae inside corals, it's not just about the critters.
If you do not replicate the natural environment for the critterts and feed them 24/7 like in natural systems, they do not produce enough N and P for the micro algae.

So rather than dealing with that, good microalgae conditions will help the critters.
Start at the base of the food chain rather than a step or two up.
So called bottom up control.

Macros will not strip a system as clean as skimmer that's correctly set up though.
But then again, less is not alway better.

Regards,
Tom Barr

Depends of the fish and bioload.
More => larger refuge is required.

Here's the deal: always construct a larger filter/refuge/or skimmer than you need.
Why? Because you can always add back things like NO3, PO4, Fe, traces etc and top off the tank's needs.

It's harder having an underpowered Refuge that never keeps the NO3/PO4 down.
There is a push pull effect with NO3 and PO4 if you watch your dosing.

Limit the NO3 sometime and you'll watch the rate of PO4 uptake decline.
Limit the PO4 sometime and you will see the NO3 uptake rate decline.

This is obvious and what anyone would normally predict, the treatment is limiting one nutrients, thus preventing trhe uptake of any other nutrients.

The entire system gets downregulated.
That's fine if you want less uptake and slower growth, but less light and PO4 pulse dosing will address that, but most think less PO4/NO3 is better, more uptake is better etc, but then do not take care of their filtering plants/macros.

How can you expect them to operate at 100% when their needs are not addressed?

I'd go with a huge refuge personally.
If you use a small refuge on a larger tank, you will not likely need to dose.
If the biomass of the macro increases 3x, the tank will still have excess available for that change in biomass.

If you add a large refuge to a mid size tankm, then the biomass goes up 3x, then you run a limiting tank and need to dose either NO3 or PO4 or both.

It depends on the system and it also depends on the assumptions of the aquarist.
Some believe in myths and faith, some test to see if these assumptions are correct or not.

I think you know which group I fall into.
And that's why I have greater flexibilty in methods, managment and general knowledge, you learn a lot more this way. If you sit and listen and don't do the homework, you will not learn as much.

It does not matter if the tank is marine or FW system, cold or warm, CO2 or not.
I can apply the methods and knowledge to any system with macroalgae and plants.

They are effective exportors, pretty, worth pursuing, andf interesting in their own right.

Being ensalved for reef filter is not their domain.
Give them their own tank and add the correct fish and critters.

Regards,
Tom Barr

Tom, don't think I flatter You, but my God! - You are really unbelievable, taking time to write down things that You've learned the hard way is simply admirable! I do now understand how You must have felt back then... Damn..


Amen!

(Though I dont get any understanding for that, most ppl over here think that macroalgae should be kept in a 50 liter fuge, underneath the show tank, inside the cabinett and behind the skimmer, kalkwasserreaktor and fosfatfilter... sad but true.) The solution to Caulerpa going sexual is according to those-in-the-know: "Keep the lights on 24/7!", or "Reverse the lightning cycle!".

And yes, the 99,9 procent of the reefppl over here test water just to be sure they are keeping low values, not to test if some theory holds, or to experiment. And when I start to tell 'em about need of the plants and algae, then the old-timers say that I am confusing the beginners and my writings in the swedish forum are "strange theories" that absolutly doesn't make sense in a saltwater tank.

Anyway, THANK You, Tom, for support with more of Your knowledge, I was almost begining to think that saltwater is really all that fancy, and that some other natural laws are applicable there, but You show that it's the same thing - sure with its own specialities - but still the same thing. Thanks a lot!

I'll be taking care of the coraline during water changes. It definitely takes away something from the look. I scraped a fair amount off before I took the photo but well, you know how tough it can be

Coincidentally, the mushrooms were originally at the spot you are suggesting. The right hand side is still planned for Halophila but I had removed a lot of macros for the LFS and shuffled the tank around. If this ends up like my FW planted tanks it will be some time before the final design starts to take shape. I've been researching what's available (and peeking in at RC and seahorse.org) so it's a case of finding the things that really catch my eye and are managable. With FW, it's so easy to pick and choose and swap plants.

I totally neglected to mention this. My 20g sump is packed with cheato on a reverse photoperiod. I still get a swing though. Around 8.2 during the day, and about 8.0 at night.

I don't inject CO2 but occassionaly use a two part supplement. I'm actually going to experiment with CO2 at the weekend. Not in the main tank though. I'll be setting up a 2.5g for the drop check method. It has me really curious.

Absolutely. Couldn't agree more.

Yep. Sarah's a plant person afterall. I was a freshwater planted person for a long time. But I was in love with biotope stuff, so I was never really big on the boards with the beautiful Amano style tanks. I still read APD. Still remember the older days, when I lurked and discussions on soil CEC helped me learn high school chemistry.

Now I try to do it both ways. Biotope, but beautious. We'll see.

I think you'll be nicely surprised with the CO2. I'm still consistently amazed at the difference it makes. And still afraid to recommend it to people who have coral they are super attached too, or have sunk a lot of money into.

>Sarah

Got the back glass cleaned of coraline at last. Oh boy that was a killer on the arms. I'll get to the sides this weeks.

So, with no PO4 dosing I'm still getting superfast growth. It's almost like nitrate is preventing the whitening tips I was experiencing, and the small amounts of traces are keeping the lush green color. I wish I could prove this outright but it's only my observation.

I'm switching out the skimmer for an internal filter in the sump. I want to test if it really is aeration that was my issue when I pulled the plug on the skimmer the other week. I can say for certain that it doesn't pull out skimmate, but it does a fine job at gas exchange. Did I experience a burst of carbon or oxygen limitation?

I also should be receiving a bag of goodies from CA within the next week. Let's hope the weather plays nice for shipping.

Stunning!! Now that you can grow stuff maybe one could add more colour to the layot, like that pretty red bush.

I'm hoping to receive all sorts of nice stuff from CA, then I can think about aquascaping a little. I've never been one to go for the well trimmed tanks on FW and I will be keeping a more rugged look on this tank as well. But yes, variety will be a nice touch.

IMO...it looks great now, as with everything else you grow
I can hardly wait to see it when you are happy with it!

Hehe, listening to Tom has its little perks.