A few questions

[m2b]

After finally spending a little time in the water this weekend, first time in two years I have several strange questions. No I don't do any serious freediving, lack of proper equipment(bad mask, wet suit, weight "belt", etc) as well as no one else in the area that does any LOCAL diving I guess you could say I go breathhold snorkeling, HA!!!

Until two years ago I hadn't did any kind of open water swimming/diving only swam in pools. Where I grew up there wasn't much opportunity for open water swimming, unlike now where ponds and lakes are all over the place. My mind is quite used to thinking in terms of pools, even though I haven't been in one in over a decade. I'm still use to thinking of being able to see the bottom while on the surface and you're only in 10 foot deep water. This alone may be why I notice what I noticed two years ago and I still notice now. What is it that causes murky appearing water even though the visibility isn't all that bad? Admittedly, your definition and my definition of good visibility is probably as different as night and day. When I use to live in Ohio visibilty of 10 feet, horizontally, would be fantastic, while visibilty of 10-15 feet around where I live now is pretty normal. I know this question sounds very strange but I'm serious. The one pond that I was diving in two years ago and on Saturday, very briefly, APPEARS quite murky. At least that is the way it seems. There is a lot of particulate matter that you see floating around the water, it is the same way in the lake I was in yesterday. In both bodies of water if I let my legs drop down, vertically, I can the bottom of my fin. I stand 6'3". The visibility is definitely better in the lake I was in yesterday than the pond that is just right downstream from the lake. The bigger lake that both the lake and pond dump into has the best visibilty of the three by way far. In that lake you can generally see bottom while still in 8-10 foot deep water. What makes the difference? I haven't been able to notice any real difference as of yet? Give me something to look for, LOL!!!

At the end of the day yesterday I noticed that at the surface you could see quite a ways, good 10-15 feet, at least. Looking down you can normally SEE THE BOTTOM until you get into 5-6 foot deep water, after that forget it. When you dive down in 8-10 foot deep water you can't see the bottom until you are 2-3 feet from the bottom. It's strange, hence why I'm asking the question. I do understand that sunlight coming down through the water would make a bit of a difference, both times I was in the lake yesterday were without direct sunlight striking the surface of the water, morning and evening.

I bought a snorkeling package at(I can already hear the screams) Kmart on Saturday, yes it did provide some interesting feedback that brings up question two. Oh yeah, I did return the package yesterday after the morning diving session, I figured I would before I ever bought it but I wanted to try a couple ideas out, one being the purge snorkle. I loved it and ended up buying it separately upon returning the package. The snorkel I had been using, how do you say homemade, was WAY to big in diameter. I could fit the new snorkle down inside the old snorkle, if that says anything. This one is much easier to clear and I do like the purge effect, for only $2.45, you can't beat the price. It definitely beats the old washing machine hose snorkle that I had been using. I do think the packaged snorkle did have a little better mouthpiece on it than the snorkle I ended up buying and using in the evening.

The package also had more flexible flippers than the Lexan monofin I made a couple of years ago. Do stiffer blades make for faster/easier finning?

I took the fins from the package and tied them together through the manufactured holes that were in the fins. It was obvious that they would work quite nicely as a monofin that way. I added a piece of rope around my ankles to make sure that the fins would stay together and act as a "one piece unit". They are a bit smaller than my homemade monofin both in length and width. They are also more flexible and have a much nicer foot pocket. When I tried it out yesterday morning, the fin seemed significantly slower than my homemade fin. It almost did seem like it wasn't "catching" as much water with each stroke as my homemade fin. How much of an difference would the flexibility of the blade make in its performance. It almost seemed like I was "sitting still" yesterday morning while trying the purchased/pieced together "monofin". I was moving very slow compared to what I normally move with my homemade fin. I realized it at the time and when I went back out in the evening with my homemade fin I confirmed the difference. Actually my homemade monofin seemed both "easier to use" and faster. Unfortunately it doesn't have the MUCH BETTER foot pocket that the returned fins had, LOL!!! I've got to work on that problem sometime. If I can just figure out a way...

How are you staying afloat on breathe up while still properly weighted? Unless I keep my legs moving they want to drop and that forces the rest of the body to want to sink. It seems that with only 3 pounds of weight, roughly, that I am having trouble staying afloat on breathe up. I know it takes around 8 pounds to keep me bouyant in about 8-10 feet of water, see question below. To get breathe up I have to keep moving my arms and legs to keep afloat. I only dive in waters where I pretty much know I'm not going to have boat traffic to deal with so I don't use any floats or anything else. I guess you could say I get quite picky on where I dive.

Right now, again with bad equipment, all the way around, I was playing around with the bouyancy factor last evening. I thought with 8 pounds I could make myself bouyant at around 10 feet, give or take on both the weight and the depth. I first tried with the 5 pound dumbell weight that I put around my waist with a bunge cord. I was still floating right back up to the surface when I stopped forward momentum. I took the, roughly, three pound window weight that I had laying around the house and tossed it down the inside of the wet suit and tried again. It worked wonders. I was staying right just dab smack up off the bottom without trying to move in either direction.

How much a of range in depth is there in your bouyancy? You are bouyant lets say at 15 feet, what is range of that bouyancy, for example 12-18 feet, above 12 you float and below 18 you sink???? What is the normal expectancy for bouyancy range? How much of a weight difference do you have to make to change where you are bouyant? What would a one pound difference typically make?

How much of a difference does a full sleeve wet suit make compared a tank top weight suit, in terms of temperature difference. Just curious. When I got into whitewater kayaking in the late 90's I bought a tank top wet suit that I have been using for diving. I know it doesn't work worth a crap. I'm only in the water for around 30-40 minutes with 60-65 degree water and I'm already starting to shiver. I'm just wondering, curious, how much should I be kicking myself in the butt for not having bought a full sleeve suit a decade ago.

I don't have the money for much of anything, hence why I jerry rig everything to make it do what I want it to do. It's that or stay home and pout, LOL!!! I'll stick to jerry rigging.

Thanks,
Ryan

[shoutatthesky]

Hi Ryan, That sure is alot of questions. I too started with minimal equipment. My first wetsuit was a $2 tank top and for weight I put stones in my pockets till my buoyancy felt at the right level. Now when I go diving I wear close to $2000 worth of gear - suit, fins, weights, camera, etc. It's great that you are not letting lack of money get in the way of going diving but I do suggest you look into getting a decent weight belt, goggles and snorkel at the very least. The type of suit you wear will dramatically affect the amount of weight you need and so will your body type, water depth, fresh or salt water, etc.
This is a good place to start http://forums.deeperblue.net/beginne...reediving.html

[rslomkow]

Lake Visibility

Lakes vary in dramatically viability!

My experience is the two biggest factors:

1) algae
2) sediment

Also lakes are not pools. They have layers. Some lakes that don't have any circulation will create dead-layers (entropic lakes) because they have no O2 in them at the bottom and nothing will live there.

Algae blooms vary with time of year and of course there are many different types. Some that grow near the surface, some in the water, some suspended in the water column.

Take a flash-light with you and see how many particles you can see. (Maglites -minis are the ones I have used underwater- are good to 30feet if you are careful, cheap flashlights in a zip-lock bag probably 10feet)

One you step on anything in the bottom you destroy the viability unless you truly have a rock bottom. So try to get off the bottom as soon as possible.

Also shore ecosystem don't look much like mid-lake eco-systems. The plants change and fewer things (frogs, fish, snakes, people) disturb the bottom.

Warmer the water the more likely algae growth is. So ponds tend to have worse visibility than lakes. Most lakes also have worse visibility where streams join them even if the stream is perfectly clear, because the running water stirs up sediment.

Hope that helps.

visibility is not an intrinsic part of the water, but its interaction with the surrounding environment.

Weighting

Understanding the buoyancy of your own lungs is something often neglected from snorkeling and SCUBA training. The average person has 6L of lung capacity and 4.8L of difference from inhale to exhale (Vital Capcity)

So you are looking at a difference of 2+ 2L bottles that you need to pull down. With you or drop, that is a lot of float. If you are diving deep it is not that big of a deal. Every 10m (33 feet) the volume will halve and you will have less "float" pulling you up. (Boyle's Law)

You can reduce the speed that you drop during your exhale by flattening your body on the surface, but if you remain in exhale you will still probably sink. It is up to you to find the right mix of wetsuit (float) and weights (sinkers) that you are comfortable diving with. In general you should be positively buoyant for at least half you dive.

Fins

Strapping two fins together generally doesn't make a good mono-fin. You should just do dolphin kick with the fins. I am not sure what kind of holes these fins had, as I have been seeing more and more cheap fins that are imitating some complicated designs (propeller/split fins which need a strong plastic ridge to provide power, but you can make fins that look like them with soft plastic, they just never work well).

Mono-fins get their power from their surface area more than their stiffness.

Stiffer fins have more "power" for the same surface area.

A very stiff fin (think Aluminum mono-fin - that the Russians used to race with) are also inefficient because of how they pass through the water, not all parts of you stroke have equal power, and you want a fin that provides resistance when you have power in your kick and not when you don't. So you don't tire yourself out just trying to go somewhere.

Softness changes the shape so you don't have lots of drag at weak parts of the kick.

But in water modeling and continuous deformation are tricky topics that nobody has really been able to model quite right yet. Not to mention people who can adapt their muscles with training to provide different amounts of power at different times. In other words nobody had designed the perfect fin yet

* Soft fins tend to have less acceleration but more efficiency
* Bi fins generally become worse when tied together, doing dolphin kick with them seperate will give you a better experience
* mono fins are generally fast/powerful because of their large displacement, small monos are not that much more powerful than two bi-fins

Conclusion

I hope you can find some information that is helpful to you on this forum, but it may requires lots of reading of the back posts.

Freediving is definitely a sport that can be done on the cheap and in your local area. Though from my experience in other sports (Mt. Bike racing, Kayaking, Fishing) the cost of getting all one rung down from pro-gear is much much cheaper in Freediving.

There are a number of people who like to build their own gear, though at this point it probably costs many times more to make your own mask than to buy one.

You can get real foot pockets for about $30 that can be glued or bolted onto your mono-fin creations.

Have fun in the water

[m2b]

Thanks for the replies back. A couple of more questions came up tonight while doing some more diving. Actually one is almost a repeat from before with some more details noticed tonight.

After I got in the water tonight I decided to do a 'fin check'. I got into deep enough water that I could stretch my leg out all the way beneath me. When I moved the fin I could see it without trying. Since the fin is made out of clear lexan any light that is available reflects off the fin and makes it easy to see. I moved out a little further into the lake and dropped down feet first and kept moving the fin until I noticed that I was moving the sediment on the bottom of the lake. At any point I could see the fin moving. I figure that would put it at an ease 7 foot visibility right there without trying. This was in a part of the lake that had seen the sun already go behind the trees. As I was finning out further into the lake I was in the usual tunnel effect, err where everything mixes in with everything else since there is nothing there to focus on. Now I know I can move my arm up in front of me if I start to lose my mind, LOL!!!, so I can put something in focus to look at other than nothing. Toward the end of the session I was finning along the surface when all of a sudden a fish appeared. I was quite surprise to see one this far away from the shore...it's been a while. I ended up hooking up with the fish and swam around with it for close to 5 minutes at one point a couple of other fish joined in. I noticed the massive difference in 'visibilty' between when the fish had the sun shining on it and when it was in a shadow. Having something in front me that I could focus on was far more inviting than it has been thus far. At least it doesn't make me think I'm losing my mind.

Are there any good tricks for breaking the monotony of having nothing to focus on?

I know freedivers typically like low volume masks. What is the performance difference between a low volume mask and a regular scuba mask? I don't have either, but I'm just wondering.

I recently saw on a state govt website about how they determine whether something is called a pond or lake. Single or multiple thermocline layers was a big factor in the difference. When diving during the mid to late summer months in the lower 48 states what is normally the coldest water temps that you would expect to see. I would think it would be in the 50-55 degree range, wouldn't it. If you dig down in the ground once you get below frostline it pretty much stay around 50-55 degrees year round. Wouldn't that also apply to water temps as well, at least during the summer months. Is it actually possible to dive down and after a ways find your in warmer water than what you was in just a few feet above.

Thanks,
Ryan

[rslomkow]

Swimming with fish is a great experience! Glad you found them.

What to focus on?

Dive down check out the bottom from up close!
Watch the light ripple through the water.
Switch on to your back and watch the clouds as you swim out.
Just pay attention to how the water passes around you.
Hold you breath for as long as you can and do just under the surface swimming.
Pay attention to how the water swirls around you.

Not sure what to tell you, I am incapable of being bored while in the water. Well I guess I have never really tried more than 6hrs alone in the water.....

What is the difference between SCUBA & Freediving masks?

For the most part Freediving masks are subset of SCUBA masks.

Low-volume serves two purposes.

1) Less drag when swimming through the water.

This is not just a "I like to go fast" issue. It also means that the mask doesn't get tugged off your face while swimming and it will leak less. It just means it is a small mask. Small masks seem to be more popular for SCUBA and in cheap snorkeling kits than they used to be.

2) Less air needed to equalize your mask.

As you go deeper you need less air to blow out of your nose to keep the mask from sucking your eyeballs out. If you are diving less than 15feet you will probably not notice this (though I know people who have gotten blood in the eyes in 15-feet with swim goggles)