Low maintenance tanks

>From: Erik Olson <olson at phys_washington.edu>
>Subject: Low-maintainance tanks
>> From: "shaji (s.) bhaskar" <bhaskar at bnr_ca>
>> I'd like to convert my 70-gallon tank to a low-maintenance, but still
>> high-tech, plant tank.  I want to do water changes and prune plants no
>> more than once a month.  I also want to keep my existing stock level
>> of fish - 0.5-0.75 inches per gallon of mostly 2-inch fish.  I still
>> want an interesting tank, with at least a few challenging plant species.
>I have kept a few tanks like this myself.  I keep high light (2-3
>full-length tubes) over the tank, and harvest floating plants (Salvinia
>and the occasional duckweed that sneaks past me) every water change. 
>Works great for me with medium fish loads.  notes: 
>   1. As you mention, the shade prohibits high-light plants.  So I keep
>an anubias garden there.  I could also do crypts.  Hey, there's a wide 
>variety of unusual crypts, enough to keep you interested, I'll bet!

Yes. I like this idea.  Mike T. and That Fish Place seem to have good
selections of crypts. Crypts would go very well with some Hygro
difformis that Steve Pushak suggested via email.

>   2. Floating plants (well, ones that have their leaves above water, at
>least) don't need CO2 injection; they get it from the air.  The low light
>plants don't really need much either.  It's my guess that the floating
>plants also keep the water still at the surface, so there isn't too much
>gas exchange there.  -> No need for that high-tech gadget. 

I think CO2 could help my crypts as well.  At least, I may be able to
answer the $1M question: does CO2 hurt or help crypts?  Actually, the
CO2 may even help the floating plants by raising the CO2 concentration
in the air above them.  Another reason why I am thinking of keeping
the CO2 is that I would like to use a few stem plants for accents.

>   3. Perhaps as an alternative to floating plants, you could grow 
>emersed plants out of the water?  They should also not need CO2 injection.
>I read about a tank done by Vinny Kutty, that had all floating & emersed 
>plants... Seemed like a good idea.

This is another possibility that I have been tossing around.  I
suggested dropping the water level to accommodate emersed growth, but
my wife vetoed that plan when she found out that she may have to give
away our Angels because they would not have enough room.  I could
always raise the fluorescent lights off the top of the tank, I
suppose, but that would leave only a few plants capable of growing out
of the tank.  I still have not dropped this plan.