How many do you require for a system? Or is it all preferential?

1 per 25gal of water will work well.

Ken

really, thats all? 1 per 25g

I'm a little confused why you guys are trying to stunt their growth and SP out of curiosity where did you read this?

More leaves means more photosynthesis which means more nutrients are needed to fix carbon dioxide into a food source. Class C3 plants don't have two ways to get nutrients, they have the pathway of photosynthesis and if you remove the light you kill the plant end of story.

A healthy large plant that has a high rate of photosynthesis requires nitrogen and other compounds to synthesis proteins (As they lack the ability to turn their produced 3-phosphoglycerate directly into a protein compound).

So as larger plants have a greater rate of photosynthesis and thus will have a higher net metabolic rate they will in turn take in more nutrient compounds from their roots. Fat people eat more food why wouldn't fat plants do the same :lol:?

1 per 25 will certainly make a dent but if you are looking for a bit more filtration you can increase that number greatly. I have around 100 running on the 350g so 1 plant per 3.5 gallons.

This photo was taken 03-28-2010
http://img42.imageshack.us/img42/3850/p1110433.jpg

and this is them right now:
http://img821.imageshack.us/img821/163/p1140271.jpg

http://img837.imageshack.us/img837/1769/p1140270.jpg

and these are the bro's:
07-06-2010
http://img101.imageshack.us/img101/3346/p1120034.jpg

09-23-2010
http://img580.imageshack.us/img580/6346/p1130989.jpg

Two other quick points:
-Mangroves replace excess intracellular sodium ions with magnesium so having a large stand of them can deplete Mg ions out of the water. Dosing a Mg supplement will counteract this.
-As Ken said spraying them down (A good 1-2 min spray down) is needed every so often. Also watch for yellowing/ dead leaves as the plant pumps excess sodium into these and then undergoes apoptosis to remove them. Make sure you remove these before they start decaying in your water.
Levi

I'm not sure I remember the exact source but this is typical advice for mangroves, I actually haven't seen much to support not pruning. Even J&L recommends limiting the leaves
http://www.jlaquatics.com/phpstore/s..._ID=i-mangrove
Not that J&L is a solid source, if I come across something I'll post. Pretty sure though that leaves need to pruned to keep up good nutrient export from the water but I'm no biologist.

J&L is pretty trust worthy so you could be right but it only makes sense to me that the larger they are the more nutrients they require to maintain themselves and grow.

Wish my mangroves grew like this, thanks for the inspiring pics levi !!

Im pretty sure that Levi is right about the non-pruning vs. pruning. Thats first year biology basically.

It is often suggested that the plant concentrates on 'expanding it's root system' when the top is being pruned (thus the root system 'taking up nutrients'), in theory if the argument is valid, I presume so that it is more capable of growing up and out when it is not being 'environmentally restricted' (pruning = similar effect to predators or crappy weather? - beings tend to secure lower more basic needs before pushing through the next steps). However, it makes sense that a plant photosynthesizing more/more effectively (one with more leaves) will be better equipped to expand its root system (because as Levi mentioned, more capable of fixing carbon dioxide, for their carbohydrate needs, food sources and cellular structural tissues. If you don't have the energy needs met to grow, you cant).

So, I can understand where the two arguments may come in, but I think it makes more sense to 'let the plant go'? Maybe someone created the pruning/root structure argument to legitimize the size control of their mangroves? Who knows?

You be the judge.

P.S. I dont prune mine either, and they are growing like champions even in a low-flow fuge full of macroalgaes.

Cheers,

Chris

looks great. lets hear all about your lighting for that crop?