Re: Cichlids and plants

[Thomas Barr <tcbiii at earthlink_net>]

> I use Excel in my East African Rift Tank.  With the high pH, you can't get
> the CO2 concentration high enough to be beneficial to the plants.  So Excel
> is the only alternative.
 
I have rift lake GH's and high KH's and plants and use CO2 gas to lower the
pH to 7.2 or so.

Check to see if the fish you have actually came from the lake or are tank
bred, check the range of habitat that you speak of. The pH is not 9.2 in all
of lake Tanganyika nor is the GH the same. There is a high variation in
location, time of year etc. A similar thing can be said for the Brazilian
rainforest. Folk's don't go there during the rainy season to collect fish.
There are seasonal changes and the animals do exist in different parameters.
pH's can drop to 7.5 in some places in the lake.

But if the salts(take a look at the salt make up in the lakes also) and ions
are at a slightly alkaline pH, the effect of adding CO2 to lower the pH from
8 or down to 7.2 is not something to worry about. Even for breeding,
sensitive species like Cryprichromis, Xeno's etc. Most of the fish are tough
tank bred cichlids. Just one of the reasons they are so popular.
Adding K2SO4 at high levels is not a bad thing either(for the plants or
cichlids). High GH also. These have fairly positive effects on plants.

The biggest issue with Rift fish are the diggers and plant shredders. Be
careful not to pamper the fish too much and limit yourself. As long as the
changes are not abrupt, most fish are quite adaptable. Wimpy fish die on the
flight or before they make it to market.

You can have a hard water plant tank or a soft water plant tank is the point
here. Some might prefer this for their Apistogramma wilds or Altums/Discus.
Some might go the other direction with AF cichlids.
You can still have plants in either tank.

Some just have to add a little K2SO4, GH builder like SeaChem's Equilibrium
or use coral in the gravel/filter etc and Epsom salt etc. I'd generally stay
away from NaCl. A tiny amount won't have too much effect but higher amount
will reduce plant leaf size, reduce photosynthesis, reduced respiration
rates, reduced stomatal opening. Note, these are general trends and not
plant specific. Practical matters say you can add a little NaCl to a plant
tank will little noticeable effect. Personally, I don't add any, never found
a need to(Diseases, wimpy fish that die if you look at them wrong etc). A
very simple but true idea: healthy plants= healthy fish.

Regards, 
Tom Barr