Re: NANFA-L-- Native Aquatic Plants (LONG)

Subject: Re: NANFA-L-- Native Aquatic Plants (LONG)
From: Todd Crail (
Date: Thu Jul 29 2004 - 17:24:15 CDT

Hi Laura,

Thanks so much for your detailed response! I have one regret from the
Convention, and that was _not_ turning around, leaving Nick and my blowhard
discussion of ethics ("So... Where _did_ you get those pirate perch!?"), and
going back through the outer garden with another plant geek :)

> I just like a nice, easy, planted tank. So please, no flaming anyone. :)

Welcome to a native fish list. You'll find people around here like the same
thing, and haven't bought $500 of heater cable for their little plant's warm
feet, so there's usually no "investment toes" to step on :)

> I don't think the bare soil has anything to do with it - I actually never
got it in my bare soil stuff. It has more to do with nutrient loading
> I have never had cyanobacteria in tanks that no not have fish in them.

This is really interesting to me, and I think may solve a critical question
of mine! I have a hunch now that the physical properties of the substrate
(sand or soil) have more to do with WHERE the cyano appears, or even better,
does not appear.

My core argument in using sand as a substrate has been "surface area". And
with that "surface area", the amount of available "mouths" to eat the
nutrition I place into the system (I'm an Armenian Grandma too :) I hadn't
realized that until just now, how light would be able to penetrate into so
much further into a white, gapped, sand substrate (with our light
intensities), than a dark, compact, soily substrate. I think that in these
sand substrates, there is an equally sized population of cyano in an equal
tank with other substrate (gravel, soil)... However, it is dispersed over a
greater area and does not materialize in the undesireable mats.

At water change time, there is a proliferation of cyano in my surface
sandbeds that are visible from the sides (never in the rainbowfish where the
top 2" is flourite), which diminish as I have removed the organic source
(either by cleaning out the pounds of mulm from a canister, or liberated
nutrients in the water column, or both). It also shows up pretty much
regularly in light films on the back glass (an area depauperate of "mouths")
and receedes after the nutrient change.

It may be suggestable that in a dark substrate, as cyano needs light, the
available surface area for the cyano to grow is greatly diminished. So it's
obviously not the substrate that is growing the cyano... It's the
substrate's physical properties that grow it in different configurations
that are seen as desireable or undesireable to the aquarist.

Ah. That feels better. Now to solve the problem of rejuvinating the
nutrients under a sand coating. It would be interesting if the reduction
performed by the growing and dying of these bacteria in the sediment bed
(reduction of available nutrients) are enough to offset the uptake by the
plants themselves. I think this will be my next aquarium.

> Aquatic and wetland plants have special adaptations to deal with anoxic

Preaching to the choir here. That's what got me started in all this plant
stuff. People were telling me that somehow plants and substrate behaved
differently in a tank than in the wild. I'm quite despondent when I get a
"do" without a "why", and it lights a match under me to figure out why it's
so unsettling :)

> Some plants like water sprite and Ceratophyllum also float and are good
nutrient removers.

I'm a huge fan of hornwort during this time (setup and establishment) as it
allows light to penetrate, and fixes a heck of a lot of nitrogen and carbon
quickly. I've used water sprite before, but it just grows too fast to cover
the whole top, which I've found just slows down establishment below.

> While sand looks nice, it also keeps mulm (containing nutrients) from the
plant roots. Some plants are pretty heavy feeders; I think Vals are one of

Yes, vals do horribly in a newly established sandbed but this is what is
weird... They jam after about 4 or 5 months (and do just fine with old
"live" sand in a new tank). This is what leads me to believe that there is
a serious amount of reduction by the sandbed organisms going on (which is
also fixing the liquid fertilizer into the substrate as well). Having the
soils and clays in there as well, can only be extremely beneficial, and may
get over the hump of 1) the low amount of nutrition in a new bed and 2)
being dependent on the fertilizer.

I've always known I've been using the fertilizer as a prosthetic, but now my
fears have been allayed about the soil causing too much enrichment, so it
will be very interesting to see if I can get out of that business. And
remember, this is the high dollar Sera stuff, not the low brow Jungle and
Tetra crap, which I agree, cause problems, especially with blackbrush and
other types of stringy, parasitic rhodophyta. It's like they have enough of
one thing, but not enough of another, so the algaes take control. I found I
was better off just adding dissolved potash (good luck finding it where it's
not sold by the ton :) to relieve the potassium limitation than using the
other fertilizer products, until I decided to give up some bucks and try the
Sera product. But I'll be a student soon, so I can think of a lot better
Christmas presents than a 2 liter jug of Florena lol

Hopefully, this will get me out of the flourite business as well. I've been
wondering about smashed clay pots (or just sushi-sized slices of unfired
clay), but it sounds as though the soil will take care of this equally, if
not better.

> OR, I've been thinking about experimenting with this in my brackish tank
(which has sand for the hogchoker)putting some plants in clay soils in tiny
plastic (homemade) pots with holes drilled in, then putting these in the
sand. We'll see. Could be a complete disaster, especially with higher
light and not enough plants.

Pick up some caulerpas and dictyota from a local marine dealer, or take a
trip down to the coast (sand substrate marshes like in Florida). A great
book for identifying them is Littler and Littler's "Marine Plants of the
Caribbean". You'll be making regular harvests, and there are some really
interesting plants (and critters living in them) in brackish/seawater. I'd
be doing the same, but that 34 ppt buffer is all that's keeping me away from
coral farming again, and with my allergy to cnidaria... That's not any fate
I'd like to tempt. My little "Inner Gollum" goes off too frequently. :)

> Good lighting is also required by many plants, Bacopa included.

I will be setting up a 100 gallon (72x18x18) with two 175 watt metal halides
as point source lighting, and then two 48" GE Daylight Ultras overdriven by
an IceCap ballast (95 watts?) to fill in lighting gaps. I have all this
crap from my reefkeeping daze... But I am sold on halides for large aquaria
as the most bang for the buck. And since I have it, I might as well use it

For the most part, however, I use just the GE Daylight Ultras-in-regular
wattage. But since this is a 6' tank, I figured I might go a little bigger
on the canopy size, get the glitter lines (can't wait to see the greensides
under these lights!) and all the fun stuff that happens with halide.

So I think in the past, my problem has been nutrition, not lighting. That's
one thing I don't skimp on, especially since I've found out how to do it
cheap :)

> I use no CO2 systems, no expensive lighting stuff, no special gravels, no
liquid fertilizers.
> AND I spend a WHOLE lot less.

I hear ya! The only thing I was stuck with was the fertilizer, and
hopefully with this exchange, I've solved my issues that get me out of that
game! Thanks again!

It's never too late to have a happy childhood.

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: Wed Sep 29 2004 - 12:21:36 CDT