水草情迷

To birdnest,
I have been dosing k2SO4 for about 1 year, no problem with fish. SO4 is a pretty safe stuff.

Btw, KCl should not be toxic too, KCl has even been used as table salt(NaCl) substitute. I once saw that in Parknshop, where there is a brand of "healthy" salt with about 60% KCl and 40% NaCl.

Oh yes, but the one found in Park'n shop are (Feed grade / Oral grade). However, the stuffs which we usually buy are agricultural grade, which contains other substaines besides Nacl and K20 i.e. Magnesium, Calcium, sulfate, chloride, bromine....varies kind.

However, i am not really sure if it will do bad on fish (long-term dorsage), but for man consumption it should be purified and pass some special treatment before using. And most important is, it depends on your SOURCE.

我用左kcl for 1 month，無發現問題。係响亞Van之前在這裏介紹的公司買的。

Alan 講得啱，d毒應該係因為有重金屬，同一條formula 中，鉀和鎂的硫酸鹽沒有用edta螯合。

btw, if any of u wanted some syringes that can measure
very small quantity, ie smallest is 0.2ml, i have a few.

個 discussion move 左過黎都唔知 tim
有冇人買倒 D 野呀
去邊買呀

Here is the address of a company that might have what
some of u guys are looking for. The company sells
chemicals/biotech equipments to the DNA research lab
in my Uni. I personally have not dealt with them though.

Below are the details:

ADVANCED TECHNOLOGY & INDUSTRIAL CO., LTD.
UNIT B, 1/F., CHEONG SHING BLDG., 17 WALNUT ST., TAI KOK TSUI, KLN, HONG KONG
Tel: (852) 23902293/ 23945546 Fax:(852)27898314
E-mail: sales@advtechind.com
Web Site: http://www.advtechind.com

Here is some price indications from an email newsletter they sent me a year ago.

Oops! The attachment doesn't appear.
I will paste it here instead.

Date: Tuesday, August 14, 2001 10:08 AM


Advanced
ADVANCED TECHNOLOGY & INDUSTRIAL CO., LTD.
UNIT B, 1/F., CHEONG SHING BLDG., 17 WALNUT ST., TAI KOK TSUI, KLN, HONG
KONG
Tel: (852) 23902293/ 23945546 Fax:(852)27898314
E-mail: sales@advtechind.com Web Site: http://www.advtechind.com

Customer Newsletter August, 2001

Dear Valued Customers,

We would like to thank everyone who has supported us in the sales
promotion last month. Our summer sales would be continued till the end
of August.

Most bio-chemicals are in stock and immediately available. Price is
attractive and the quality is better when compared with the equivalent
products from Sigma, here are some examples:-

Part no. Products Packing Our Price (HKD) Sigma Cat. No.
Sigma Price (HKD)
0710-100G AGAROSE I BIOTECH GRADE 100G $763.00 A9539
$952.00
C4036-1KG CESIUM CHLORIDE MOLECULAR BIOLOGY GRADE 1KG
$2,830.00 C4036 $3,317.00
AC07261000 CITRIC ACID MONOHYDRAGE, MOLECULAR BIOLOGY GRADE
1KG $195.00 C8532 $259.00
0105-1KG EDTA, DISODIUM SALT, DIHYDRATE, BIOTECHNOLOGY GRADE
1KG $412.00 E5134 $498.00
1042011000 GLYCINE GR 1KG $930.00 G7403 $1,385.00
0826-1KG TRIS, BIOTECHNOLGY GRADE 1KG $443.00 T6066
$530.00
167620010 TRIS (HYDROXYMETHYL) AMINOMETHANE, BIOCHEMICAL GRADE
P.A. 1KG $1,350.00 T6791 $2,156.00
443827W SODIUM CHLORIDE MOLECULAR BIOLOGY GRADE 5KG $426.00 S3014
$512.00
811030-1KG SODIUM DODECYOL SULFATE ULTRA PURE 1KG
$1,850.00 L4390 $2,450.00
1030951000 SODIUM PHOSPHATE, DIBASIC ANHYDROUS 1KG $685.00
S3264 $923.00

For details, please do not hesitate to contact our sales department on
2390 2293.

Advanced
ADVANCED TECHNOLOGY & INDUSTRIAL CO., LTD.
UNIT B, 1/F., CHEONG SHING BLDG., 17 WALNUT ST., TAI KOK TSUI, KLN, HONG
KONG
Tel: (852) 23902293/ 23945546 Fax:(852)27898314
E-mail: sales@advtechind.com Web Site: http://www.advtechind.com

Genomics One Products

Introducing the Unique TrueBlue® MicroCartridge(tm) PCR Cloning Kit
<<ole0.bmp>>

Genomics One has combined TrueBlue®, the only cloning system to offer
100% accuracy in clone selection with the ready-to-use MicroCartridge
Reagent Delivery System to offer you the most advanced and most reliable
PCR cloning kit ever!

Get 100% Accuracy In Your Next Cloning Experiment!

Based on its TrueBlue® Technology, Genomics One has generated cloning
products designed to cover the entire spectrum of capabilities needed
for efficient genomic and general DNA cloning work. Here is some
examples:-
Catalog # Description Ligation Time Size of DNA Insert
Applications Unit
TBC0110 TrueBlue® MicroCartridge(tm) PCR Cloning Kit Minimum 10
minutes up to 2Kb All PCR Cloning 10 reactions
Catalog # Description Copies per Cell Size of DNA Insert
Applications Unit
TBP0527 pTrueBlue® Plasmid 200-500 up to 2Kb Multi-purpose
Cloning 10µg
TBR0546 pTrueBlue-rop® Plasmid 15-20 up to 10Kb Large cDNA & PCR
Cloning 10µg
TBB0539 TrueBlue-BAC2® Plasmid* 1 Up to 300Kb Genomic Glycerol
culture
Libraries
TBM0013 M13TrueBlue® Phage 200 up to 3Kb Shotgun
Sequencing & Site-Directed Mutagenesis 10µg

For more information, please contact our sales department on 2390 2293.

K2SO4, KNO3 ARE strong acid

TO ALAN2002,

你個LIST O的 CHEMICAL 唔平 WOR, 買晒咁多就~~~~~

To Tam:
K2SO4 and KNO3 are not acids.
Acids always have the H+ ions, and the acidity comes from the
dissociation of the H+ ions (which is a strong oxidizing agent).
A strong acid has almost 100% of its Hydrogen atom going into solution to form the H+ ions. (By the way, pH measurement actually measure the concentration of H+ ions in water, ie, it is expressed as the molar concentration of the hydrogen ion as pH= -log[H+], so more H+, pH drops)

I think u r refering to the H2SO4 (sulphuric acid) and HNO3 (nitric acid). They are strong acids!
H2SO4 --> 2H(+) + SO4(2-) (in water, almost 100% dissociation)

Yes right, they are not acidic.

However, KNO3 is listed as category of dangerous product in Hong Kong.

To Tam,
They are not cheap bec of the purity, ie, biotech grade,
agriculture grade/industry grade is cheaper. Maybe they will sell in smaller quantity??

For me, i can't be bother to diy the trace elements mix, just buy commercial preparation, much cheaper and less troublesome. I just diy the macros. Trace elemnts i am using Azoo's, b4 i use JBL.

To Bird Nest:
KNO3 is an ingredient for making explosive. That's why is restricted for sales.