1 In general, the total dissolved solids concentration is the sum of the cations (positively charged) and anions (negatively charged) ions in the water. 2  Parts per Million (ppm) is the weight-to-weight ratio of any ion to water.  A TDS meter is based on the electrical conductivity (EC) of water.
Collard greens may be worth considering for health additions to your diet. These dark-green leafy vegetables provide iron, vitamin K, folate, calcium and the antioxidants lutein and zeaxanthin. They may even help you prevent gout or reduce your symptoms when you eat collard greens in moderation as part of a healthy diet.
Answer Wiki. I will assume you mean green iguanas. This species is 100% vegetarian, so their diet should consist of fresh greens, vegetables, and (to a lesser degree) fruit. But they cannot live on lettuce alone, so which greens and vegetables you feed should be picked because of their nutritional value. Below is a list of good foods from my blog, Much Ado About Chameleons. Do not use cheap iguana pellets from the pet store or insects.