Lately it seems like there's been a lot of debate whether plants like swords and crypts, etc, actually need root supplements, or will do just as well with only water column dosing. I've always taken it for granted that they did need it, but Ive never actually tried any of them without it.
Inspired by a recent idea from Hoppy in this thread
, I decided to set up an experimental tank and try to find out if "heavy root feeders" actually deserve the name.
The Plan is to divide a standard 20 long in half at the substrate level, using a 4" tall piece of plexiglass, siliconed in place. Both halves will be inert Black Diamond blasting sand. One side will have a heavy application of Osmocote Plus, the other side will have nothing. Use the same plants on both sides, EI ferts, CO2, medium lighting....and let's see what happens!
Here's the empty tank with divider siliconed in place. I though it was important to have it sealed around the edges, otherwise roots could creep through the cracks from one side to the other.
On the left is brand new blasting sand, never been used, with nothing added to it. For the right side, I put down about 1/2" of sand first, then loose Osmocote Plus, then added the rest of the sand on top.
Depth is about 2 1/2" in front, and about 3 1/4" or so at the back.
*Note: The right side is sand I had already from another tank. There's about 20% regular black aquarium gravel mixed in. It sifts to the top so it looks like there's more than it really is. I dont think it will be a factor.
All planted -
(Left to Right)
Back row - Argentine swords, A. reineckii (not the mini)
Middle row - Crypts: Green Gecko, and Im not sure on the next two. I think a Wendtii red or bronze, and a Wendtii brown. Hygrophila var compact.
Front row: S. repens, DHG, P. helferi
Both halves are identical.
The four swords are all babies off the same runner.
Dual Aquaclear 20s. They were both running and cycled, so hopefully any nts/diatoms etc can be avoided.
EI via liquid solution mixed per Zorfox's recipe
for 20 gal.
Two T8s in a homemade box with pretty good reflectors.
One Hagen Life-glo, and a 5000K "plant bulb" from Wal-mart.
60-ish PAR seems about right. It's a little less on each end because the bulbs are only 24" long (tank is 30"). Hopefully the stauro wont mind being in the 40s. It's about the same front to back, very little difference.
DIY sugar/yeast, using two 2 liter bottles diffused via both Aquaclear filters.
Chopstick pre-diffuser -
The system should be legit as long as I change one bottle every week and dont get lazy. Ive ran this same type set-up on a few tanks now - all with way more than 60 PAR. For more details like how the bottles are sealed, etc, see the diy link my sig.
I'll take some PH readings in a day or so to see what kind of drop is going on.
About 20 guppy fry from two different sets of parents....and a handful of snails. Im hoping the snail population establishes. I like snails as long as they dont get outta control.
So that's where it stands as of now - day 1.
Hopefully this will turn out to be useful and interesting. I'll try to post updates every week or so.