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Re: Sand in the substrate... (with UGF plate) , Aquatic Plants Digest V3 #1409

| Date: Tue, 23 Nov 1999 15:05:53 -0800 (PST)
| From: samm <wmaster26 at yahoo_com>
| Subject: Sand in the substrate... (with UGF plate)
| I am considering sand in my new 55G tank and I have
| two questions:

I have used sand in the past and really prefer a small 2-3mm aquarium
gravel.  Sand tends to accumulate fish mulm (fish crap and decaying plants)
on top because it is so compact and
will not allow the mulm to sink through and quickly becomes unsightly.
Small gravel allows the mulm to permeate the top layer and reach plant
roots over time where it is most beneficial.  Heavily planted tanks rarely
need vacuuming assuming fish load/feeding are minimal.   Sand in the lower
layers of the substrate will become tightly compacted preventing nutrients
from reaching roots and trapping toxic gasses and other nasties turning
"foul" and requiring replacement.  "Sand" typically has a very low CEC.   I

MHO, I would forget the idea of using sand as the predominant or only
substrate material all together.

| 1.  I read the archives and am now quite confused as
| to  the brand and # to buy.  The only store available
| here is Home Depot.  Could anyone please specify a
| *brand* (I heard something from Texas???) and a #
| (also, what does this number specify exactly???)  Is
| there a difference in construction vs. sand-blaster vs
| other sand???

Tex-Blast refers to a manufacturer of sandblasting sand used by car body
shops and other application for mechanically (using a high air pressure)
removing paint and other surfaces off a variety of things including car
bodies. The "#" refers to the grain size.   It seems Tex-blast is an
inert, course, quartz (cheap!), gravel that is not too small (as compared
to sand in the sense/size of say beach or play sand) and works quite well in
planted tanks providing you get the right size.  Getting a hold of Tex-Blast
seems to be regional and is cost-prohibitive to ship it all over the
country.  I could never find Tex-Blast years ago when looking for it the
mid-Atlantic region of the US.  Your better-quality LFS (not the national
chain-stores) will carry good 2-3mm aquarium inert gravel in bulk or at
least have the good 2-3mm size in large 25 and 50lbs bags for a decent
price.  I always say you can judge a good LFS by the price of their gravel
because they respect the fact that any hobbyist in their right mind is not
going to pay $1/lbs for gravel.  Even Seachem's Flourite is cost prohibitive
for larger 100+ gallon tanks!  I think I have 225lbs of gravel in my 125g!
Just keep searching for the right gravel at the right price,  you will find

| 2.  For those who have a UGF (or RUGF) plate under the
| sand...how do you keep the sand from going down under
| the plate (is there a specific # on the sand..please
| specify brand).
|     I have heard of people using fiber-glass sheets???
| (where can they be purchased??? and please mention any
| specifics in terms of diameter of the holes and so
| on...)
|     Others I have heard use a thin layer right bellow
| the sand which keeps the sand in place...anyone have
| experience with that???  what material do you use???

Holes??   Anyway, UGFs have long been regarded as NOT very useful and
non-conducive for long-term, stable (like 5+ years without total tear-down),
planted tanks by many plant tank novices and experts, although quite a few
people still use them. An UGF effectively becomes both your biological and
mechanical filter which harbors lots of bacteria under the plate and
requires frequent cleaning.  This is hard to do in a heavily planted tank
and unnecessary when you compare it to a good canister filter.  Many
ions will be oxidized to unavailable forms with all that well-oxygenated
water flowing through the substrate, and the plants will suffer.

RUGF are typically very slow-flow implementations that theoretically cycle
water column nutrients (and fertilizer additions) through the gravel where
they can be utilized by roots an/or become bound in the substrate by the
cation exchange processes.  RUGFs also may equalize the temperature between
the substrate and the water column avoiding the "cold feet" syndrome and
similar to the effect of Under Gravel Heating Cables.

IMHO I would definitly bag the idea of both UGF/RUGF because the space under
the plate becomes very full of detritus, the flow rates prevent efficient
utilization of nutrients by plant roots.  May I recommend a simple
commercial laterite mixed into the bottom 1/3 topped with the remaining 2/3
small 2-3mm clean (aquarium gravel).  Some like to add a small percentage of
natural sphagnum peat moss for added CEC and it's effect on slightly
lowering the pH of the substrate.

| Bonus question!
| do you find it better to cover the sand with a thin
| layer of gravel??? (especially for fish that like to
| munch on the gravel and play around...and also does
| the sand alone keep the plants rooted well--especiall
| if you want to do some re-arrangements...
Bonus answer!  See two previous non-bonus answers.  If you need sand to help
anchor your plants your using too large a gravel size.  If you keep fish
that "like to munch on the gravel and play around" you will be fighting an
uphill battle keeping you plants rooted long enough to send out roots and in
general a decent planted tank.  Try to stick with fish that are not
aggressive gravel diggers and keep small cory's and plecos like the
bristle-nose as scavengers in planted tanks.

| Thanks,
| samm  Los Angeles

Your welcome :)
Tom in Virginia (dreaming of my favorite thanksgiving dinner of Royal Blue
Discus stuffed with Riccia-Japonica dressing.....mmmm! :)
drummore at ix_netcom.com