hey man, found this also, might help.
Ph Problems
One of the first signs of having a slight ph problem is, your plant having part of the leaves kind of twisty, spotty with brown, yellowish, red spots within each other.
Sometimes they don’t have to have all the colors, they could just be spots that have yellowish brown, or just reddish brown and can happen anywhere on the plant. Mainly starts on big fan leaves then goes to little leaves.
When this happens you need to check your soil ph, water ph before and after adding your nutrients. One of the biggest causes is adding nutrients like earth juice; they take the ph down quite a bit. Also can happen when you add bone and blood meal to your soil, that will throw the ph off as well, so it’s smart to test the mix before putting your plants into the mix. After the spots happen you will soon see nutrients being locked out, when that happens DO NOT ADD ANYTHING TO FIX THE PROBLEM UNTILL YOU GET YOUR PH FIXED!! Reason why is, because the plant isn’t absorbing that nutrient, by adding the nutrient it is deficient in, you are causing it to have a build up in the soil therefore can cause that nutrient to become toxic to the plant, because of buildup, to much buildup of certain nutrients will lock out other nutrients. In order to fix the problem you will need to first fix the ph and then if the soil is deficient in nutrients you can add it to fix the problem. A digital PH tester is the best tester to use as they are the most accurate. If you can’t afford a digital ph meter, then your best bet is to get ph testing papers. DO NOT get soil testers, those are the cheapest junk I ever seen and do not give good readings, so you cant rely on one of those. There are a lot of good ph testers out there, one of them is hanna. That is the one I use and is the best money ever spent! Vast majority of problems with soil ph comes from the soil if it has additives like peat moss, which is HILGY acidic..... and or the water you are using, as well as nutrient deficiencies from using the wrong ph for watering. You want to be careful when adjusting your ph, doing this over a week is the best idea, to fast will cause shock to the plant. If you can’t get a hold of a ph tester or ph test papers. If you have some dolomite lime, its always better to use it in soil rather than every time you water, imo and from others (Uncle Ben) That it really doesn’t stabilize as many people think it does, Soil pH and micronutrient availability are interrelated. Don’t Use to much lime to decrease the soil pH to a point where micronutrients can't be unavailable to plants. The micronutrients affected by pH include iron, manganese, zinc and, not as often copper. The problems when you apply to much lime can make it harder to correct your ph than what you would have when you didn’t add as much lime. You can always add more lime, but if you add to much you can’t remove it if you put to much lime in the soil. With great soil moisture, lime will work immediately and pH will start to change over a few months. However, it can take up to a year for the real benefit of lime to work. As the soil pH rises, the time it takes for lime to react decreases due to lower levels of soil acids. If you need to change your ph when its to high, if you choose to use lime it will not help as much as you think in lowering your ph, it would need alot of lime to lower your ph to a point where it would cause a toxcicity to the plants so look else where to use something to lower your ph rather than using lime.
So here at the bottom is a list of some buffers that are good to go with when raising and lowering ph!
Here are some ph buffers when your ph is too high: Use these SOIL PH Adjustments to lower your ph: sawdust, composted leaves, wood chips, cottonseed meal, leaf mold and peat moss. Sawdust, composted leaves, woodchips and, lemon juice, PH DOWN.
Hydro PH Adjustments: PH Down (vinegar and lemon juices are good for soil, but not recommended for hydro use) Phosphoric acid during flowering and Nitric acid for vegtative growth.Thanks goes out to syko2 for that one! (Only quality PH buffers should be used to adjust ph and be sure the buffer and nutrient work's well together.)
Here are some that will raise the ph: use these SOIL Adjustments when your ph is to low: PH UP, dolomite lime, hardwood ash, bone meal, crushed marble, or crushed oyster shells, potassium hydroxide <--- Thank you Uncle Ben!
Hydro Adjustments: PH UP,lime,potassium hydroxide and potassium sillicate .(Only quality PH buffers should be used to adjust ph and be sure the buffer and nutrient work's well together.)