There are two things to consider when buying an anchor: boat size and bottom conditions. The size of the boat determines how big (heavy) the anchor needs to be, and the bottom conditions determine the anchor style. The weight of the anchor can hold a boat in calm waters, but in most conditions you will need to make sure the hook is well set, and hooks are designed for various bottom surfaces.
https://www.getmyboat.com/resources/boating-how-to/136/choosing-the-right-anchor
Boat Anchor Material Types. Boat anchors come in a variety of types, the most popular being mid steel, high-tensile steel, stainless steel, and aluminum. Most of the traditional steel anchors we are accustomed to seeing are likely either mild or high tensile steel.
http://www.anchoring.com/blog/anchor-selection-guide-choosing-an-anchor-type/
Increase the size if 1  –. You have a heavier boat than the average. 2  If you have lots of windage i.e. a big solid fly bridge, a ketch and etc. 3  You are a big wide boat.  You have a big blunt bow on your 1  boat. You are a nervous sleeper or are 'out to lunch' when you are asleep.  You have a lightweight rode behind the anchor.
http://www.chainsropesandanchors.co.nz/what-size-anchor
First, there is the physics of anchoring, such as knowing how heavy an anchor needs to be to secure the boat. Next comes the technique of “setting the hook,” or getting the anchor to hold. Regarding the latter, there are as many opinions as there are boats.
https://www.getmyboat.com/resources/boating-how-to/136/choosing-the-right-anchor
Anchor Selection Guide: How to Choose the Best Boat Anchor Type. This entry was posted on February 19, 2014. There are a number of boat anchors available, constructed of different materials, and often with confusing names.
http://www.anchoring.com/blog/anchor-selection-guide-choosing-an-anchor-type/
Some use five pound anchors on 30 foot yachts and anchors big enough for yachts on canoes. Some toss anchors over the side, then realize that the anchor wasn't attached to its rode. Some drop anchors over the side with rode, but without a knot at the boat end.
http://www.finefishing.com/1freshfish/aahowto/boating/anchors.htm
Always a great question to ask and watch the discussion fire up when you do. Anchor systems work in such a variable environment nobody can give you a direct size guide as such. To download a PDF version of this article click here. Note: The following is meant as a guide only and is a bit generic. If you are not sure ask us or someone else with more experience than yourself.
http://www.chainsropesandanchors.co.nz/what-size-anchor
At least 75 feet of rode is a must to set anchors on smaller bodies of water if you use the seven to one rule. You may need 100 to 150 feet to even 200 feet of rope to safely anchor out in deeper water.
http://www.finefishing.com/1freshfish/aahowto/boating/anchors.htm
All Fortress products are manufactured in the USA. 1  Boat anchor size recommendations are for boats of average windage and proportions in 30 knots of wind, average bottom conditions, and moderate protection from open seas. Remember that the loads in 42 knots of wind are twice as much as in 30 knots.
http://fortressanchors.com/selection-guide/fortress
This article will discuss the most popular types of boat anchors, the most common material types, and also give an overview of different naming conventions. Our video below introduces many of the anchor types discussed here, although the article discusses a few more anchor types and gives some useful links.
http://www.anchoring.com/blog/anchor-selection-guide-choosing-an-anchor-type/
how big of an anchor
An anchor is 30 knots of wind.