Discussion: Are we obsessed with circulation and flow?

[plantbrain]

I think Diana Walstad originally thought that a filter and water circulation wasn't essential for the low tech. planted aquarium, but after further experimentation changed her mind and recommended both some form of biological filtration and method of water circulation.cheers Darrel

Well, for a low light, non CO2 system, that gets few uprooted plants, disturbances, sure.

As you drive things faster, higher rates of growth, more fish, CO2 enrichment, this model changes.
It can still work also, but it's much less stable than say a non CO2 planted tank.

Many seek stability, some like very little labor, input, then such non cO2 tanks are very well suited.
If the goal is more about gardening, horticulture, then more light, more CO2, more nutrients will be required, and then diffusion becomes more relevant.

Something in between, perhaps Excel, easy Carbo, low light etc. Moderate to low flow etc.

These things are interconnected.

Regards,
Tom Barr

 

[plantbrain]

Algae isn't about too much light vs nutrients, CO2, flow etc, is it not about the ammonia levels?

Did Tom Barr not say that ammonia is the algae trigger, so healthy plants = little to no ammonia as the plants are taking it up before any algae can take advantage...

Is the wpg rule not also tank size dependent? As in smaller tanks need a higher wpg ratio compared to larger ones?

Or I may be missing something.

I use PAR, not WPG, never liked that unless I knew the lights and the tank personally or had direct experience with the brands etc.

NH4: this is true in higher light systems, less so or not much at lower light.
It's not an on/off thing, it's a gradual effect as you increase things. I think there are other factors involved certainly.
In general, NH4 seems to be more a green water bloom inducer, not much else, maybe staghorn and finally a little BBA.
I've not been able to induce any other species with NH4Cl or (NH4)2SO4 or with over loadign fish/shrimp progressively.

So it's not a model by itself, light(in PAR) and CO2(very good measure) must be included there.

Nor does it explain all the noxious algae species, but I do not expect it to either.
With good plant growth, there really should never be any NH4. We can dose it, but at long as it's 0.8ppm per day or less, things seem fine in most aquariums where the other factors are somewhat independent.

Hopefully that clarifies?

Likewise, decreasing CO2 seems more of an issue and adding more light etc.........this yields a strong effect and a stronger cure when reversed.

Regards,
Tom Barr

 

[plantbrain]

This is one reason I like low-tech., changes tend to be slow and this gives you more time, and more of a chance to rectify things before they get out of hand.

cheers Darrel

Good advice, re read it a few times if your not Darrel

I like lower light and low tech tanks me self.
It shows maturity, thinking, patience, and a rich reward.

This tank gets little flow(3x an hour):



These fish are fairly good for this tank size(38 gal).

In another tank, I added CO2, but the light about 10 micromols higher:


I can grow any species, but like the non CO2 tank, I still have easier to manage growth and if something does go wrong, I'm still fine and no issues. This tank has about 400gph on a 60 gal, so ~7X an hour.
I use a small Rio pump in the upper corner, and the wet/dry pumps about 300gph through.
Fish load is about 90 Brass tetras, who have high O2 demands and 11 Leopard frog plecos, 200 RCS, fairly high bio load.

Tank is very easy to care for, I trim once every 2-3 months at most.
Water change etc, takes me maybe 15min a week of work.
The non CO2 has never had a water change.

Regards,
Tom Barr

 

[flygja]

Came across this article on TFH. http://www.tfhmagazine.com/blogs/?p=329

Sounds like a recipe for disaster! 2x turnover, 298W of lighting which equates to 4 wpg - of which there are 10,000K and even actinic tubes and NO CO2. He says there are about 125 fish and 30 shrimps in the tank. And yet the tank has been running for 2 years.

I'm amazed but I don't think I'll try it!

 

[beeky]

I'm a great believer in keeping tanks clean and I think high flow/filtration at 10x helps to achieve this. It's definitely possible to have lower flow like Amano and others as long as you're meticulous in removing dirt/detritus. In the marine world high flow has been found to be necessary for corals in order to keep detritus suspended in the water column for subsequent removal. Once it starts settling it blocks pores and ammonia is produced within a thin layer over the "host" (I can't remember the term now for this layer unfortunately), causing damage and producing algae.

I don't believe it's all about removing ammonia directly but removing the source of that ammonia from the plants themselves.