Category Archives: Gear & Tech

1 MICROSCOPY – Tutorial

1) Microscopy Tutorial



Tutorial Contents

Unboxing the Scope

The Optics (Magnifiers) 

The Screen on the Scope

The Stage & Its Adjustment

All About Lighting and Adjustment

Adjusting the Lighting and Focus

Using Practice Slides to Focus 

Sample Collection (Several Methods)

Skin Biopsy

Gill Biopsy One

Gill Biopsy Two

Intestinal Snip for Worms Etc.

The Parasites Overview 

Flukes Under The Scope

Costia Under The Scope

Ich / White Spot Under The Scope

Chilodonella Under The Scope

Trichodina Under The Scope

Miscellany and a 5 Minute Biopsy Collection Video 


Why the Celestron? 

It’s the best scope you can get, for anywhere near the price. It’s got a mechanical stage and a video screen PLUS video capture and the whole scope is less than 175$

The intent of this tutorial is to teach hobbyists how to use a microscope. This is not a five minute thing to learn. So if you’re in a rush, skip it.

Necropsy Video

Necropsy Video – Necropsy, Biopsy, Injection and More

This is an old video, but cutting off a fishes’ head isn’t something that goes out of style. The techniques demonstrated are gross. And not everyone does these things the same way. All fish involved in the video were DEEPLY if not TERMINALLY anesthetized. For example, the fish we decapitate was motionless with no gill movement. It was DEAD.

There’s an amalgam of videos here, some of the videos are my hands, many are most obviously not. The ones with the pretty fingernails are not me. Ha ha ha ha.

Sound was edited out of the video in case you’re banging on the sides of your computer speakers to hear some sort of audio.  lol

A Good Food To Make Your Medicated Food On. 

Making Medicated Food
If you're going to make a medicated food using the following tutorial [Making Medicated Food] I recommend you build the food on the pellet at right because it is specifically engineered to bolster the immune response in fish under attack. It's very palatable and holds up well in the process. I've used this food to make the medicated food shown in the tutorial. 
I suspect any food would be okay, but I don't know that the other foods would still float after treatment.

BlueRidge Probiotic
This particular food is made with hyper supplemented levels of vitamin C and some nucleotides that have been shown to bolster the immune response.

The Ultimate House Call Kit

The Ultimate House Call Kit

I think it would be cool to have a house-call Dodge van, shaped just like a fish, and maybe five porters to carry my gear, but I travel, and I need my gear to be SMALL, so I put together this kit to use for seminars, pond calls, pet shop visits and trips to the wholesaler. It has just about everything I’d need except for ‘general-anesthetic-surgery’.

Minor surgeries, sure.

The kit is based in a box by Pelican. It's got two latches. They make a larger box with four latches but you just don't need a box that big.

Inside the kit are:

Test kit strips
USB Camera for microscope
Syringes and needles
A power outlet divider
A desktop lamp
My pointer
My thermometer
My oil of cloves
Slides and coverslips
My Swift FM-31 Field Scope (tiny!!!)
Nitrile exam gloves
Practice slides of Frog's Liver
Ziploc bags for samples, holding fish and mixing OOC

Here's the Swift FM-31 set up with the USB Camera mounted onto the eyepiece. I mean, you CAN use the scope without a USB camera but it's murder on your back perching over the thing. The USB camera attaches to your computer with a simple USB interface.

This one's smaller and the one I'm getting this year:

In case light is scarce, I have this little desktop gooseneck lamp for pinpoint lighting on what I'm doing. If the wet lab is in a darkened room, I can light up my work area without illuminating the front row lol. I leave the light in the box until or unless I need it.

This is an infra-red thermometer, which is used in the food industry to check temperatures on serving trays. You can check water temperature without contaminating a thermometer. Or bending over ha ha ha ha.

When you're teaching someone how to use a microscope, I like to have a box of "practice slides" which are made professionally and feature something like "frog's liver' and a person can truly SEE that they're adjusting the scope. When you start out looking at water, with bubbles in it; it's difficult to tell if you're in focus or not. Maybe the scope's broken?

These three bottles have been replaced by Tetra's new "EasyStrips Complete 7-in-1" test strips. They got them down to two sleeves sold in the same kit. Nice. I'll bring these to the seminar in case someone steals a can of strips, it wasn't expensive lol

You will think of a hundred uses for these on a pond call. But mainly I can hold a small fish for injection through the bag, and I can mix up an emulsion of Oil of Cloves without having to carry a jar with me! I can also collect a sample of water for later if I need to.

The sooner you get over to these type of aquarium heaters, the happier you will be

erik johnson podcast
This 400W titanium heater knocked the bottom out of the titanium heater market arriving twenty dollars under the nearest competitor with twice the power and 5 star reviews. I use them everywhere in the office and at home.

I have owned just about every kind of aquarium heater over the years from the ancient glass hang on heaters to the newest titanium bodied heaters. The price on the titanium heaters has come down to one that is very reasonable and fully worth it. Have a listen to my brief podcast on choosing an aquarium heater and why you should consider buying titanium.

erik johnson podcast



Making Dechlorinator – Sodium thiosulfate

How should I make a good dechlorinating solution? I have read about some pretty high doses, like 250 grams in 500ml of water to make a stock solution.
A: First, let’s tell our reader how to get dechlorinating granules, Sodium Thiosulfate:

See below for link to find like, 5 pounds of sodium thiosulfate for overnight delivery.

If you put 130 grams in a liter jug, then add water quantity sufficient to make 1 liter, your stock solution will contain 130 grams/Liter.

Each teaspoonful [5 cc] will contain 650mg active Sodium Thiosulfate. This is a 13% solution.
Simply add 2 drops of the stock solution per 1 gallon of the body of water to be treated . One liter of your solution can treat 10,000 gallons. Over-dosage is virtually impossible.

Another method with the same results is to put 500 grams in a gallon jug, q.s. to 1 gallon then you have the same 650mg per tsp. [13% solution] Add 2 drops of the stock solution per gallon.
One gallon can treat 37,850 gallons or more. 

Why you need dechlorinator (Click)

Making Dechlorinator – Sodium thiosulfate


Heron and Deer Scare That Works Every Time

You can make a Heron and Deer Scare That Works Every Time for about $70 with materials you get on

 It’s pretty simple to make and it relies on LIGHT and A LOT OF NOISE to scare off a critter. You need the following:

  • $15 – 5 Gallon Bucket with lid (Green’s nice CLICK)
  • $25  – Black and Decker Jigsaw WITHOUT BLADE and handle taped ON (Click)
  • $15 – Motion Detector Floodlight that takes Standard Spots.  (Click)
  • $8 – A Light Socket to Outlet Adapter (Polarized!) (Click)
  • A drill to put some holes in the bucket
  • $15 – Stainless Steel nuts and bolts. (Click)
Deer and Heron Scare You Can Make for $70 Works Every Time
Click for giant printable version


Dr Johnsons Koi Health & Disease Textbook Available Near You

Seller Price – Seller rating

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Barnes & Noble$39.99 No rating$119.00 No rating

AbeBooks$45.55 No rating

The Aquadyne Bead Filter

This is one of the filters which I [Dr. Johnson] have used extensively at my home*. I still have a 2.2

*Aquadyne 2.2 on 1,000 gal water   (2018)

Where to Buy: With a Return Policy (Thank you, Amazon!)

Bead filtration appealed to me because prior to bead filtration, I’d been using sponge filtration, matting filters, and lava rock filters. These filters ALL worked super. I have no complaint about these filter types as far as keeping fish healthy and I show you all these designs in this web site! I am not condemning the technologies.
BUT, when it came time for filter cleaning, I was completely miserable. The sponges weighed a ton, got me filthy and dirty, and always spoiled the water when I put them back in. The matting filter was not as bad, but it didn’t work as well as the sponge filter. The gravel filters I was using were great, but man that gravel wore out my fingertips at cleaning time. And it made a fetid mess.

*Since then I pay someone for the effort.

Needless to say when I heard about Beads, I was “all about” a filter which was easy to clean and would work better than anything I was using before. Or so they said. But it turned out to be true – Bead Filters work great. And nothing wears out, the media isn’t expended or short lived!
I have used about seven different models or brands of bead filters over the years including the Bubble Bead 1, the Bubble Bead 2 and the FluidBead, HydraBead, Challenger, Aquadyne 2.2, and Aquadyne 4.4.
That’s been sort of an odyssey, because each filter has it’s drawbacks. A major plus to Aquadyne is that there’s no “plumbing” inside the Aquadyne. It’s made on a computerized machine and not with 2″ PVC either.
Okay I won’t continue to bore you. You should just look at the guts of the filter and you’ll see the difference. GUTS
Aquadyne isn’t a sand filter or hacksaw and glue bead filter. It’s a patented design which has given me NO trouble over the last six or seven years.
Anyway, the Aquadyne has been working at my house for about six years now. I’ve used their 2.2 and the 4.4 and now I use two, tandem 4.4 filters. I truly believe in “overkill” when it comes to the media. It doesn’t cost much more for the extra capacity and the practice of oversizing a filter at startup anticipates that fish grow prodigiously.
The Aquadyne is a major advance in bead filtration. It was one of the first filters to use a multi-port head and gives easy access to the beads unlike the older Bubble Beads. I am very fond of these filters. 
The Aquadyne filter is retailed at various outlets including They have a money back satisfaction guarantee which is a good thing when trying something out for the first time.
I am impressed by the AquaDyne for several reasons:
Using a multiport inlet, they have a rinse feature which allows you to discharge the first few gallons of water returning to the pond after cleaning.
Because of the filter body being used for this design, there is also a bypass feature which allows you to continue the un-interrupted flow of water, but the water completely bypasses your bead cake. This can be a priority when using short term medications such as Formalin which could negatively impact your filters’ biological bacterial flora.

Aquadyne Filters 4.4 Size
I had two of the Aquadyne 4.4 filters on a facility in Blue Ridge Georgia long ago.

Also, the AquaDyne has NO elbows inside. The patented “column” inside is a stroke of simple genius. The column is made of precision, machined parts and cannot be copied by a hobbyist for a home-made version. There are several design concepts which are so axial that unless a person had a fully equipped machine-shop, they could not reproduce this “column” at home.
The absence of elbows allows massive throughput of water. I was amazed to see that the filter throttles the flow down to 1.5 inches at the head, but returns through a two inch pipe at a rate sure to please anybody. Now, the AquaDyne can ship with an even higher efficiency head. This unit has four throughput pipes.

*I have used (and endorsed) other filters but this was based on their performance and not their longevity. One of the filter-types I was using ended up clogging and had to be completely disassembled for cleaning. It’s the dumbbell shaped one*. My first introduction to Bead filters.

*since then, air wash technology is available for Bubble Bead filters.

The next kind of filter was snazzier but it ended up choking on its own check-valves. Never buy a filter which relies on internal check valves. They always fail.

Aquadyne Cleanout Super Thorough

“The Big One” Super Cleaning Method.

This is the “Big One – Annual Super Cleaning Routine” I perform once per year on mine.

Before you stop the pump, open the sludge drain near the bottom of the filter (it’s a ball valve) and note the amount and type of discharge. I have met people who have NEVER opened this sludge drain! Close the sludge drain as soon as the water runs clear-ish.
Stop the pump.
Open the ball valve on the blower riser.
Put the control head to “Backwash”.
Start the blower.
Count to “seven-one-thousand” (Seven elapsed seconds if you have a timer)
Stop the blower.
Turn the control head to “Rinse”.
Start the blower again.
The filter should shake, rattle and jump now.
Run the blower until water stops coming out of the filter discharge line.
Or, stop the blower after 4-5 minutes.
Close the ball valve for the blower. You’re done with the blower functions.
Have the control head set on “Backwash”
Restart the pump.
When discharge starts running clear, stop the pump.
Reset the head to “Rinse”
Restart the pump.
No water will come out the discharge line for a while. The filter is refilling.
When water starts coming out of the discharge line – stop the pump.
Reset the head to “Backwash” again
Start the pump again, on “High” if it has this setting.
When discharge appears to clear, stop the pump
Reset the head to “Rinse” again.
When discharge line is clear, stop the pump.
Reset the head to “Filter”.
Restart the pump.
THEN DON’T FORGET TO: Open the sludge drain once again while pump is running and marvel at the ‘crap’ that blows out.
Parts identification image:

Activated Charcoal – Carbon Filtration (Purification)

Activated Carbon – Charcoal

Activated Carbon – Detailed information – by Carl Gittings
This article was prepared by Carl Gittings in preparation for Koi Camp 2002 at Ashland Berry Farm.
Activated carbon is currently used in numerous applications ranging from the decolourisation of sugars and sweeteners, gold recovery, colour/odour correction in wines & fruit juices, to the treatment of drinking water. Even the ancient Egyptians knew of the beneficial properties that charred coal had in improving the quality of drinking water.
Activated Carbon is typically used in three different areas of aquaculture: 1) taking impurities out of water as it is brought into a facility; 2) removing halogens (any of the five elements fluorine, chlorine, bromine, iodine, and astatine that form part of group VII A of the periodic table and exist in the free state normally as diatomic molecules); and 3) removing color and metabolic by-products in re-circulating systems.
What is Activated Carbon?
Activated Carbon is a crude form of graphite and is commonly made from wood, coal, lignite and coconut shell. The imperfect structure of activated carbon, which is highly porous, is what differentiates it from graphite. These pours range in size from visible cracks and crevices to microscopic dimension. This structure gives the carbon its very large surface area, which allows the carbon to adsorb such a wide range of components. Activated carbon has the strongest physical adsorption forces or the highest volume of adsorbing porosity of any substance known to mankind (5 grams of activated carbon can have the surface area of a football field).
How is Activated Carbon Made?
A substance is first subjected to a heating process called carbonization. This forms a fixed carbon mass that is full of tiny pores. It is then activated by a second heat/steam treatment (200 -1600oC) while regulating oxygen level. This is what creates the huge internal pore network and imparts surface chemistries that give carbon its unique filtering characteristics. There are 3 main forms of activated carbon: 1) Granular – irregular shaped particles ranging in size from 0.2 to 5mm, 2) Powder – pulverized carbon, 3) extruded & cylindrical in shape.
How Activated Carbon Works
Activated carbon removes organic compounds from aquaria by adsorption and absorption principles. Both processes involve the transfer of the pollutant from the liquid phase (water) to the solid phase (carbon). Adsorption is the primary sorption mode used to remove pollutants. This attractive force forms a bond between the carbon and the adsorbate (pollutant) causing the adsorbate to adhere to the carbon. In addition, bacteria will colonize the outer surface of the activated carbon and consume some of the sorbed organics. The bacterial action also reactivated a small portion of the carbon and perhaps prevents desorption.
Absorption refers to the diffusion of a gas or compound into the porous network where a chemical reaction or physical entrapment takes place. Ozone for example is absorbed into activated carbon where it oxidizes a portion of the carbon’s surface. Ozone (O3) is reduced to oxygen (02) thus detoxified and made safe for the pond. Ozone does not accumulate or build-up in the carbon structure.
A third process called chemisorption forms an irreversible chemical bond between the carbon surface and the adsorbate. Pollutants are tightly bound to the sorbent.
All three sorption processes occur simultaneously in the pond. The sorption process takes place in three stages:
1) Organic laden water contacts the activated carbon particle.
2) The adsorbate diffuses into the porous network.
3) Sorption onto the carbon occurs.
These activities can be described as the activities observed in a parking lot. Vehicles (organics) are moving freely on the main highway (pond water). The vehicles enter the lot (pore) in search of a parking space (sorption site).
Benefits of Activated Carbon
Due to the sorption process that occur with activated carbon, it is very effective at removing toxins (insecticide and plant), some chlorine and chlorimines, and organics that may discolor your water. The overall result is an increase in water quality. The by-product of better water quality is healthier fish. The activated carbon should have a macroporous structure, Low Iodine number which is a measure of the microporosity (below 600) and a high molasses number which is a measure of macroporosity (above 400).
All carbon will release some phosphate. It is best that one looks for an activated carbon that has not been activated using phophoric acid. Phosphate levels released by Carbons that were activated by means other that using phosphoric acid are low and not harmful to the pond or its inhabitants.