Maven

(I posted this on plantedtank.net. I know the doctor posted on these boards (somewhere) as well so I thought I'd post it here also as some of you might be interested in this.)

Recently a doctor who takes care of his own large planted tank in his office made a post asking about the grade of the ferts Greg Watson sells. Greg Watson posted and said he buys agricultural grade chemicals in bulk. The doctor said he was uncomfortable with the fact that the impurities in the agricultural grades are unknown, as are their levels. Probably fine for agriculture, but he had rare fish and plants and wanted a better grade.

Most everyone attacked him, saying he was bashing Greg Watson and that he was an idiot for even thinking this mattered. The conversation wasn't even allowed to continue and the thread was locked.

I think it's a sad state of our hobby when new ideas get attacked without hesitation. I think it's a sad state of our hobby when certain people's words get taken as gospel without even an ounce of skepticism or questioning. Some of these certain people are even downright rude in character (I think you know who I mean).

I for one wanted to try ACS (American Chemical Society) grade chemicals for myself just to compare the difference in the agricultural chemicals I already have on hand from gregwatson.com.

It was suggested that the "end customer" can't order ACS grade chemicals as they are regulated by Homeland Security and the DEA. I found out that this isn't true. Many large lab suppliers won't sell chemicals to the end customer, but there are those who do and they aren't breaking any laws. I found one and ordered some reagent ACS Grade K2SO4, CaCl2*2H2O, and MgSO4*7H2O.

Here are some of the differences I noted:

• With the Greg Watson chemicals, the formulas that were discussed and posted on the boards never quite yielded the expected results. For example, Hypancistrus, KevinC, and some other people got into computing dosages based on atomic weights. I think it was Hypancistrus who concluded that 79.39 milligrams of CaCl2*2H2O and 33.27 milligrams of MgSO4*7H2O will raise GH in 1 gallon of water by 1 dGH while maintaining a 4:1 ca:mg ratio. When actually doing this, my test results never quite matched this. For example, when dosing my tank at a water change (I use RO/DI water), I would compute dosages for raising GH. I target 6 dGH. But when I test after adding, I found that sometimes I would need to add 80%, sometimes 60%, or sometimes more, like 120% or 140%, to obtain my targeted dGH.
  
  With the ACS chemicals, I found that the dGH increase EXACTLY matched the computations. I calculate and measure for 6 dGH, and the test results return 6 dGH. So far it's been consistent with 3 water changes.
  
  This does lead me to question the purity of agricultural CaCl2 and MgSO4.
  
  
  
• One thing I immediately noticed is that I didn't even have to stir to get the ACS chemicals to dissolve. I bought a stirrer after reading about them on the boards. When I measured the CaCl2 for example, poured in some water, and brought it to the stirrer, I found that I could see no solid pieces in the container. Just pouring in water was enough to get it to dissolve completely. I am not sure if this means anything significant, it is just a difference I am pointing out.
  
  
  
• Finally, a picture comparison. This is K2SO4. These pictures were resized and sharpened a bit, but the color is unretouched. All pics were taken under the same lighting in the same position.
  
  
  
  Greg Watson agricultural grade K2SO4:
  
  
  
  
  
  
  
  Reagent ACS grade K2SO4:
  
  
  
  
  
  
  
  Greg Watson agricultural grade K2SO4 - 1 teaspoon in 200 mL RO/DI water, on stirrer for 10 minutes:
  
  
  
  
  
  (The stir bar in the bottom is magnetic. The black specs on the stir bar must be a type of magnetized metal. The other stuff on the bottom is unknown matter which doesn't dissolve.)
  
  
  
  Reagent ACS grade K2SO4 - 1 teaspoon in 200 mL RO/DI water, on stirrer for 10 minutes:
  
  
  
  

I would like to emphasize that I am NOT "bashing" Greg Watson. I have never talked to him but from what I understand, he is a hobbyist like the rest of us and he's very nice. He says right on his site "these are for agriculture," he's not misrepresenting what he is selling in any way. The only thing he's doing that I think will eventually get him into trouble is he's shipping Potassium Nitrate via the US mail, which is a BIG no-no. He may just not realize the folly in doing this if he gets caught. He needs to switch to a carrier like UPS for this and he has to designate the package as a hazardous material (oxidizer). It's not me, that's just the rules. I don't like them either!

For me personally, I don't view my hobby as "growing weeds." I go nuts over the rare stuff and I don't mind paying extra to get it. That's part of the fun for me. This goes for plants and fish. One argument is "the unknown impurities are just trace elements so what's the problem." The doctor said it best, it's that the impurities are unknown and so are their levels. From what I have discovered above, I believe the levels of impurities in these agricultural chemicals is not as insignificant as believed. With reagent ACS chemicals, I can control the trace elements because I can remineralize my water with highly pure salts, then add a trace mix (I use Flourish) where the "impurities" and their levels ARE known and have been "tweaked" for planted aquariums. So, I have decided I am most comfortable with these reagent ACS chemicals.

I doubt the Doctor will visit the boards again after the extreme negative response he received, but if by chance he is reading, I'd like to thank him.

If you do a little searching on the net, you can get Reagent ACS chemicals for lower prices. Yes, they are more expensive than Greg Watson. Many people think a product is evil if it is more expensive. But then again many people love Amano and his products are probably some of the most expensive in the industry. Again for me personally, I don't mind paying a bit more. I initially bought small quantities, but they can be found for $30 - $40 per 5 pounds (which as most of you know will last a LONG time).