Thinking 懐かしい

????

Now theres a word we need an English equivalent to.

Why is my native language so incomplete? 

I want my money back!

120 Things in 20 years is slightly disappointed!

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Filtering Poo with Continous Flow Media Bed

My indoor system started out with a gravel bed. After repairing a leak in the 45 mil EPDM liner of that grow bed, I decided to go with a Deep Water Culture (DWC) raft.  With only one 10 wall glazed my grow bed is 30"x10 long which is a rather small 25 sq ft..  I found it easier to utilize that precious space with a  raft system.

A panoramic view inside grow room.  800 gal fish tank on left grow bed on right

But loosing the large media bed meant that I would also lose the filtering capability of the 3/4" rock media.   So I decided to build a filter using evaporative cooler pads.   This works great at first, but after a few months the fish population began to grow and the fish got bigger.   The filter could no longer keep up with the poo.   Cleaning filters everyday was more work than I was willing to do.

So I decided to return part of the bed to a gravel media, and keep the rest as a DWC grow tank.

The DWC tank with gravel to the right of a plastic fence partition

I built a partition out of plastic fencing and PVC pipe.  Filled one side with 3/4" gravel and extended the return water pipe from the fish tank so that it dumps on top of the gravel.   One thing Id like to say about that is I also used 2" pipe rather than 1-1/4" because the smaller pipe tends to clog.

At this point I began to have concerns about a continuous flood gravel bed.  RupertofOZ was kind enough to dispel my fears by pointing me toward a very good experiment done by backyardaquaponics.com.  

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Projectiles Building a blow gun with laser sight

I thought Id build a blow dart gun with a laser sight.

It turned out to be a total success.

It works well, and is much more fun than regular darts of the non-blown variety.

I started with a couple of pins, some string, some cotton, and a thin pipe. A broken car aerial works well, so does a pen casing. Even a drinking straw works at a pinch. The longer the better, and its best to avoid flexible things as your pipe. Drinking straws tend to be a little less accurate.

I started by piercing the string so I had four strings stuck to my pin.

 I taped up the strings so they wouldnt move when I started to wrap them.

This next bit is really important.

Add a loop of cotton running the length of the pin.

Take some cotton and wrap it tightly to make a binding along about a third of the length of the pin.

I also made one where I used electrical heat shrink instead of cotton binding. It worked well, and was much faster to make, but didnt look as nice as one with binding.

Trying to tie off  the end of a binding is difficult unless you have that loop we added.

To finish your binding, pass the loose end through the loop.

Then pull the back of the loop all the way back. This will draw in the lose end, and secure it by tucking it under itself... under the binding.

Thats really important string tech. As long as you plan it beforehand and add that loop its easy, but without the loop, its next to impossible.

 The end result looks something like this.

Next I took another pin and frayed the string.

Wool would work better, but I didnt have any.

When its fully frayed, it looks like this.

You can us it like this, but it was a little slow, and not very accurate.










I trimmed mine down a bit.











The point of the tail is to create drag so it flies straight, and with the sharp end up the front where it belongs.

If you have even one thin strand longer than the others it can cause trouble.

A long strand will make your dart turn off course a bit, and can also get stuck between your lip and the tube, resulting in a blowing noise but no shooting.

An easy way to trim it is to put it into the blow pipe and cut any excess with scissors.

Next, I found my container full of prototyping plastic. I explain it in this post about its possible use in making hand made fishing lures, but basically its stuff that gets soft at 65 degrees centigrade or so, and sets hard once it cools.

Next, I got hold of a laser pointer ($15 or so), then it was a simple matter of heating up some prototyping plastic, and wrapping it around both the tube, and my laser pointer.

I added three screws that sit through the plastic so I can tighten them against the laser to adjust where it points in relation to the tube. That way, its easy to adjust and make certain everything lines up properly.



I shot some video while I was sighting it. I placed the laser sighted blow dart gun in a clamp, and repeatedly shot it, and adjusted the screws to get it more accurate. A simple matter of firing, then moving the dot to the same spot as the dart hit.

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Epic adventurer Solar boat trolling motor

I got one step closer to setting out on my zillion mile epic adventure on the mighty Murray river, on my little solar powered boat.

That step included testing just how much juice I was going to need to run the trolling motor, and seeing if the solar panel I have will provide enough.

My boat is a displacement hulled catamaran. That means it doesnt do the skimming across the top of the water thing that most other racing cats do, so its very outdated for racing, but it floats well, and the hulls are very low drag.  At their widest, they measure only 20cm or so. They are 4.2m in length, so they slide through the water without a lot of effort. Probably even slicker than a kayak.

The result of all this is that I can tick along at walking pace with an electric trolling motor on its slowest setting.

I like walking pace.

In fact, aside from jet aircraft pace, and insane motor bike pace, walking pace is my favourite pace.

So I think, the result of all that is that I should be able to power my little boat with my single solar panel. That question has been nagging at me for ages. My solar panel says it delivers a maximum of 230w at 37v and also mentions 7.5 amps or so.  I think that means that at 12 volts after an MMPT solar charge controller, it will offer the battery a maximum of 19 amps. Probably much less.

But...

I just put my trolling motor in a bucket of water (large bucket) and ran it through my multimeter. As far as I can tell, it draws around 12 amps on the lowest speed setting. Ill be taking a 120 amp hour deep cycle lead acid battery. From memory, before I had the solar panel, that battery gave around 5 hours cruising when I ran it down to 11v. But my memory is terrible for stuff like that.

Also as far as I can tell, I think that means I should be able to cruise for a reasonable amount of time each day. Theres also the option of running a bit faster during the middle of the day, when my solar panel is generating the most power. It would be nice to leave the battery with a healthy amount of charge at the end of each day so that I could use some for light, charge my phone and UHF radio, and to power a laptop so I can get some blog posts out.





Ill probably want to set up camp each afternoon when there is still plenty of light, and get up early each morning to pack up camp and get under way when the river is at its best. If I leave a full battery at the end of each day, I should be able to set off at first light, and then make up the charge by the end of the afternoon.

Or something.

But I have no idea how this will all pan out in the real world.

What I need is a 36v to 12v MMPT solar charge controller that actually works, and wasnt sold to me fraudulently by that trader on E-Bay.

Now I dont trust the world any more.

But Ill probably get over it.

But on the up side I now know how much current my little trolling motor draws, and Ive also found a brand new way to inject a lot of oxygen into my fish tank very quickly, and perhaps mince fish.

Which is nice.

This is the trolling motor on its highest speed setting.

Excited water.







120 Things in 20 years thinks its found the worlds fastest way to empty a large bucket of water all over itself and its shed, without actually picking it up and tipping it over itself.

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Swimming With The Fish

I hope to set up a small pool this summer.  I would like to incorporate what Ive learned about water chemistry and create a natural swimming pool with plants and fish rather than chlorine or salt.

Click Here for a Slideshow of Beautiful Natural Pools

Here is one of my favorite videos

Heres a report about the added value to a home with a pool. Notice the 1000 to 2000 square foot range.

Go Figure

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Thinking Baby spinach with blue cheese and a drop of lemon

Baby spinach with blue cheese and a drop of lemon is really nice.

A small amount of cheese on a leaf like a cracker, add another leaf and a drop of lemon juice.

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