[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Aquatic Plants Digest V4 #508

> Subject: plant recommended for barckish water & pH 9
> Our lab has about 80 tanks (10-50 gal) where we keep the African cichlid
> fish Haplochromis burtoni. The water in the tanks has a pH near 9 and
> contains cichlid salts with a temperature of 80 deg F. It's total alkalinity
> is around 240 ppm CaCO3. One of our fish rooms has 18 50 gal tanks connected
> in series with a large filtration system. We are getting great aerobic
> nitrification, but have about 120 ppm NO3. Changing the water doesn't seem
> to help much. All the tanks have bright broad spectrum fluorescent lights 12
> hr/day. I would like to set up a tank to keep some plants which would
> consume nitrate and phosphate in the water to compete with algae growing in
> the water and the walls of the tanks. Can anyone recommend a plant which
> would grow well in brackish alkaline water that would consume NO3? Fast
> growth is not a problem. Do you think "hornwort" could survive in these
> conditions? What about "elodea"? Also, do you know where I could get aquatic
> plants that have now been grown in tanks with other tropical fish? My boss
> is worried about viruses and bacteria from other fish species infecting our
> fish. Thanks

If your purpose here is to remove Phosphates and Nitrates then a plant
filter would be more effective than submersed  plant culture. Plants need
three things to grow effectively with a few exceptions..........
CO2 is one of them and there are a few plants that can use the Carbon on the
CaCO3, you really would be better off not going this route for a couple of
reasons. One is your CaCO3 will be removed(think PH and buffering). Two is
these plants can grow a decent clip but do you want to trim them often? They
will grow faster if they are supplied with gas CO2 also.

A plant filter is a simple hydroponics set up with a plant grown immersed in
some media that the influent is moved through and the waste are extracted by
the plant's roots. The plants will grow much faster since they have no limit
on the amount of CO2 and O2 they available to them. A small amount of light
is all that may be needed and if there's enough in the lab that spills over
then you may not need any.

Dips can rid most of the bacteria and viral sources to your tank but good
tank health will help the most since a healthy animal is far less likely to
get a disease. I like using the animal and plant's own immune systems to
combat disease and algae. Diluted Bleach(also lime) is a good dip as are a
few other oxidizers/ Check APD archives for more info or the Krib.com.
Little would make it after being added to a a PH of 9 from most plant farms
and heavy salt content:).
Tom Barr

> - -- 
> Michael Vagell, Ph.D.
> Fernald Lab
> Stanford University
> Jordan Hall, Bldg. 420
> Stanford, CA 94305-2130
> Work Tel. (650) 725-6362