What's the Best Ph Up and Down to Use?

GH PH DOWN is made from phosphoric acid, which makes your reservoir pump and hoses slimy, especially during flowering. When the phosphoric acid hits the P saturated solution, a plume of phosphorus hits the water and the solution cant hold it all, some of it changes form to a solid and it becomes slime that sticks to everything it touches. I use sulfuric acid and I get no slime at all, all I have to do is rinse out my system once a week, almost no scrubbing at all.

You can get sulfuric acid at any auto parts store, just ask for battery acid. Cost is anywhere from $3.99 - $5.99 per liter, very cheap. You have to ask for it, they keep it behind the counter. Wear rubber gloves and goggles while handling it. For weaker strength, use 1/3 of a cup per gallon. For normal strength use about a half cup per gallon. Make sure you use RO water or distilled water. You dont want the chlorine from your tap water interacting with the sulfuric acid. A $3.99 container of battery acid will make about 8 or 10 gallons of PH Down.

Interesting! I found that my rez and tubes had a bit of a slimy feel to them and thought it might be some kind of fungal infiltration or bacteria, but I guess it's just the pH down. I recently asked for battery acid in Auto Zone and boy did I get an evil stare. So some have mentioned that using sulfuric acid could pose a potential health hazard from smoking or ingesting buds grown in water adjusted with H2SO4; I'm not sure why this would be the case? Does anyone have any good scientific evidence one way or the other?

My chemistry may be a bit rusty but I believe it would dissociate into a sulfate ion HSO4- and a hydronium ion H3O+. Hydronium ions are extremely reactive and will protonate most things they come into contact with. H+ ions are wht make solutions acidic, so a hydronium ion can easily release a proton into most solutions which will raise its acidity. This is basically the same mechanism of action as most acids. This leaves the HSO4- anion. Whether or not this would have any affect on health I don't know. The acid is being used in such minute quantities to adjust the pH of the water, and who knows whether it it is even being taken up by the plant's root system. I doubt that it would really have a deleterious affect on plants or human health at these levels, but I may be wrong. We need a real chemist to step in here. I could potentially see something like hydrochloric acid not being the greatest thing for your plants due to its dissociation into Chlorine anions (similar to bleach); chlorine is not the greatest for plants and roots.

ok-

so what is the difference with phosphoric acid?

Mad Farmer Get Up & Get Down (pH Up & Down) are some of the best (& cheapest) pH up and down products available. I have been using them for years... WHY?
1. There are 3 pH buffers in each - In the pH down there is citric acid, phosphoric acid, and ammonium sulfate. In the pH up there is potassium carbonate, potassium silicate, and potassium hydroxide. Many pH adjusters only contain 1-2 buffers, which leads to crazy fluctuation of the nutrient solution. The 3 buffers make the Mad Farmer pH up and down very stable and I don't see much fluctuation in levels.
2. There are no dyes of food colorings in the Mad Farmer pH up & down! This is actually important to me, as I don't like putting food coloring in my food, why put it in my plants?! GH adds orange and blue dye to their up and down. The dye doesn't add any benefits, its just to differentiate which one is which! I figure, if you can read a label, you don't need the dyes!!
3. MF is super concentrated! I usually only have to use a couple drops or so in a 60 gal res., so it lasts forever!
4. Its cheap!

All the Mad Farmer products are super clean and work really well. Has any one tried any of their other products? They are one of my favorite lines of supplements.
http://madfarmerproducts.com/

I have used GH and Advanced Nutrients Ph up and Down. I recommend using GH if you have a small res.. like 10 gallons or under. Advanced is super concentrated and thats why its more expensive. It can be hard to use because a very small amount goes a long way. Its awesome for 20+ gal res. In 5 gallons, litterally a drop of AN will change your pH by .1 Its at least 10x more concentrated that GH. However, in my easy cloner, GH can be easy to manage because its more diluted.

Update: For PH UP I now use food grade POTASSIUM hydroxide which is potassium based lye. Potassium hydroxide is also a hydroponic fertilizer and it is an excellent blossom booster.

You can get it here CHEAP!! http://www.essentialdepot.com/servle...ash/Categories

I bought 4 pounds of it for 12$ and it should last me at least a few years. A tablespoon makes a gallon. A bit more if you have a large reservoir, a bit less if you have a small reservoir.

As far as people being intimidated by battery acid, it is what they use in commercial hydroponic greenhouses for PH down in food production. Phosphoric acid will not work as an electrolyte if it contains impurities. Battery acid is RO water with 100% pure phosphoric acid.