KH and Eheim report

["Sharon Stewart" <sharon at stewartcentral_com>]

First, I need to offer a much-belated thank-you to George Booth for
offering advice on my KH woes. I've been dealing with sick kids and a
tank set-up, so I'm up to my elbows in AP digests.

(A correction to the below stats, btw. I wrote that my light is 55
watts, when I meant to say 110.) I find it interesting how water can
differ from house to house. Back in the fall, I tested my neighbor's
water (houses were built at the same time 8 years ago, same city water
source). My KH was 3 and his was 5. 

The reason I thought I might be seeing biogenic decalcification was that
what is happening in my tank matched the description I had read. That
coupled with the fact that all of my neighbors complain about too much
calcium in the water, yet my snails have dissolving shells makes me
think that something is happening to the calcium in my tank.

On a different front--A month or so ago I was asking for some feedback
on Eheim filters for my 110 gallon tank. I decided on the professional
II model 2028, which I set up this weekend. I couldn't be more pleased
with it at this point. It is so quiet. The tank is directly behind a
couch in the TV room and you can't even hear a gurgle from the filter.
Wow, fully loaded, this is the heaviest filter I have ever owned!

I ordered the filter from Big Al's. It was my first time ordering from
them and there were a few hiccups, but their customer service department
was great. Some of the filter media didn't arrive and there must have
been a problem with their shopping cart--I was sent an additional filter
(Fluval) that wasn't on my order confirmation but was on the invoice.
They are sending me a return sticker for the extra filter. As for the
missing media, (two boxes of the substrat), they shipped it immediately
so I would have it in time to set up my tank for the weekend. I was very
pleased with their response and will definitely order again. Mistakes
happen; it's how they are handled that matters the most.

Sharon--who had to drive 25 miles this weekend to find a store with
fluorite in stock.

---

Subject: Re: Not Co2 again!

> Date: Mon, 30 Dec 2002 19:06:03 -0500
> From: "Sharon Stewart" <sharon at stewartcentral_com>
>
> Well, I find myself in need of setting up my Co2 system on my 38
gallon
> tank. I'm having wicked pH problems, <sigh>. The parameters are:
>
> 38 gallons
> 55 watts compact fluorescent
> tap KH 2, sometimes 3
> tap GH 6 now, usually 8 or more in the Spring-Summer
> tap pH 7
> tank KH-2 for a day or so after water change, not measurable after
that
> tank GH-6
> tank pH, see below
>
> I change the water weekly. By the end of the week I have no KH that I
> can measure, and the pH swings up during the day, and down at night.

I would guess that you have very little KH (in terms of "carbonate
hardness"
or concentration of CO3). A KH test kit is actually measuring total
alkalinity, of which carbonate hardness is only one part. For example,
phosphate in the water will add alkalinity. In my experience, carbonate
hardness (CO3) is "used up" very slowly, if at all, so what you are
seeing
change is not really KH.

> And should I be adding some baking soda to up my KH? And, if I should
> add baking soda, how long will the effect last? In other words, how
> often do you have to add it?

Yes, add enough baking soda to give you 3-5 degrees (50-100 ppm) of
alkalinity. Add a little, measure, add more if needed. That should last
until you do the next water change, when you need to add enough baking
soda
to compensate for the lack of KH in the fresh water you are adding.

> I've read everything I could get my hands on and my head is swimming,
so
> any advice is appreciated. I'm guessing that I'm seeing biogenic
> decalcification, but that is only a guess.

No, it's probably not that.