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Re: Aquatic Plants Digest V4 #1496

> From: John Russo Jr <jr at medcomres_com>
> Subject: Re: KH=1
> Thanks for your advice on my KH question. I tried it and
> overshot the KH by
> a lot. The discus and angels were not too happy, but survived.
> My goal is a
> pH of 6.8 and a kH of 3, based on the earlier recommendation I
> received
> here. I would like the CO2 to be 15 ppm.

I'd go 20-30ppm of CO2. Your going to under shoot your CO2 some
of the time unless you have lower lighting or under calculate
your CO2 levels by taking the reading only at night before the
lights go off (CO2 uptake by plants will reduce the CO2 level at
this point in time). The fish can tolerate a range of CO2. At
higher lighting values the plants do need more CO2 than
10-15ppm. I'd error on the higher value. This will not effect
the fish.
> Do I have to do the baking soda titration in my show tank? It
> doesn't seem
> that I can adjust the  KH in the water in the storage tank I
> use to change
> 25% of the water in my 75-gal show tank 3 times a week,
> because the pH will
> be too high. 

That is what the CO2 gas is for, it lowers the "ambient pH" of
your water down to the 6.6 pH range from about 7.4-7.8.

>For example, I added baking soda to the 25 gal of
> water in the
> storage tank and achieved a KH of 5 and a pH of 8. I am under
> the impression
> that I should not then lower the pH with Seachem's Acid
> Buffer. Is this
> correct?

NO! Your not getting the idea with using CO2. You use ONLY the
baking soda AND then the CO2 to drop the pH,
Go back and look at the pH/KH/CO2 table off the krib. You are
only given 3 things there. Acid "buffer" is not among them. So
do not use it.

 Yet, if I don't do this, the KH of the water I add to
> my show tank
> will be very high, putting me in the same dangerous situation
> I was in after
> I first added baking soda.

Well not really but the fish might like high KH values although
a KH of 5 is not "high" per se. The danger is only getting water
than is too hard for your fish to bred but they will do quite
fine at that KH for many years.
Plants? They could care less. All that they are concerned about
is the CO2 level. So it doesn't matter if your KH is 3 or 15 for
them. As long as they have the corresponding pH adjusted
down(6.4 and 7.2-7.3) by CO2 gas, they will be happy concerning
this nutrient.
> It seems that neither of my choices are very good. With
> frequent water
> changes, I will be titrating KH in the show tank all the time.

You mean adding both baking soda and acid "buffer"? Well you do
not need to add the acid buffer and getting the KH to 3 is
pretty easy after a couple of times. Don't forget to check the
tap water every so often. It'll change every now and then.

> If I add the
> baking soda to the storage tank, I will be adding water at a
> high pH to the
> show tank. I am afraid that this will lead to the frequent
> water changes and
> extra aeration I just went through. What am I missing?

Well water changes are fine but some possible the reasons for
all the water changes are overfeeding the fish in order to plump
them up for breeding, therefore your have loads of waste in the
water, plants can remove this waste up to a point......when NH4+
levels get to the point where you start seeing a residual
present...algae will creep in. Most planted tanks are under
stocked relative to the plant mass in the tank. Fish waste(NH4)
in these tanks are quickly uptaken by the plants. So are the
NO3's and PO4's and the other plant nutrients. So if your fish
load relative to your plant load is good(favoring the plants)
and well balanced then you'll have little problem and need to
change the water far less often if the plants are kept happy.
Plants will clean your water for you _if_ you keep them healthy.
Once a week should be plenty then.
Algae/accidents/new uncycled tank is the only other reason to do
that many water changes in a densely planted tank with CO2 good
lighting etc.
The NH4 issue with an over stocked tank can be dealt with by
using a wet/dry filter also. These will rapidly converty
This is a good argument for using a wet/dry in a planted tank.
Plants can use both nutrients but NH4 is much more an algae
inducer and is more toxic to fish and most animal life.
Small trace or less amounts are preferred in planted tanks. NO3?
Well in a large number of tanks NO3 is _added_. You'll see loads
of post about KNO3. NO3 should be kept below 15-20ppm with about
5-10ppm being the better range. If you find that the NO3's creep
up to 15ppm or higher by week's end then you'll need to do more
water changes to knock it down to 5-10ppm. But if not, there's
little reason to do a water change. If the NH4 is not present
and the NO3 are under control, there not much reason to do the
water change that I can see.

As far as pH shock, I've done 50% water changes with Discus for
many years. They always looked happy afterwards. Temp is perhaps
the biggest issue. I don't allow for more than a 10F difference
in the replacement water if I can help it. If all you have is
cold tap water etc then 1/3 tank water changes is better or slow
refills etc.  

Go back and review the table on CO2.
Consider your fish load and fish goals(breeding etc).
If your goal is to have 9-12 Discus in the tank and breed them,
well I'd pass on keeping a fully planted tank. Five fish? That
would be fine depending on how much you feed them. 

> Confused in New Jersey
> John Russo, Jr.

Tom Barr 

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