Welcome to the "Who's Who of WAMAS"! Each issue of WAMAS Waves introduces you to the more personal side of some of our members. Please help to keep this column alive by answering our call for submissions CLICK HERE.CHAD, Newsletter Committee Organizer
My worst aquarium hobby purchase was an aquarium controller. Contrary to its promise, it made my tank more unreliable, less stable, and led to several near disasters.I started out in marine aquaria about a year and a half ago. I purchased a running 26 gallon FOWLR from craigslist. Nothing complicated; everything was HOB. It was easy to take care of. The previous owner gave me a test kit I used for pH and nitrate without any issues. I topped off the water the old fashioned way and ran my tests weekly. Everything was five by five.I met a fellow enthusiast through my daughter's scout troop and he mentioned aquarium controllers. My eyes became wide with talk of instant notifications and automation galore. I admit I am a gadget freak and have been DIY'ing since I was a kid. All of a sudden my sweet, innocent, low maintenance aquarium had the potential of a RadioShack 300-in-one project box. I picked up the next controller I could find on WAMAS and then the great decline began.Automate top off? No problem.Automate lights? Same deal!Feed cycles? Who wouldn't?But wait, my pH is not as "good" as I had hoped. No big deal, I'll just control the pH by dosing kalk... dissolves in RO... that will fix my pH "problem."Well. I think we all see where this is heading. In a few days I ended up with a near salinity crash , but wow, was my pH spot on. This was followed by another near miss when I mis-calibrated the probe. I got so wrapped up in the parameters that I neglected basic principles. Mainly, if the tank looks healthy, don't mess with it. Controllers give you data but you are not legally compelled to act on it. Also, your best time to add a controller is when your tank is doing well so you know the data it is generating reflects a healthy tank. Then you can observe the trends rather than absolute values. Finally, if you go with a Neptune Systems product, make sure and read the "Best Practices" thread on reef central and have someone check your program before you start.Have I learned my lesson? Kind of. I still tinker way too much with the tank, but for the most part I let the controller do its thing and I err on the side of less is more. I feel controllers are a valuable tool for the novice but just remember to resist the tendency to over-intervene.I leave for Afghanistan in a few weeks and my wife will be taking over the tank with some help for the next six months. I will not be surprised to return to a flourishing tank that was happy to have some relief from my constant attempts at "improvements."
Eheim 3581 Automatic Feeder
DIY Automatic Feeder for Aquacontroller
One of my goals in designing my aquarium was to make things as automated a possible so that I could spend less time working to maintain the tank, and more time enjoying it. I use an Aquacontroller to control the lighting, temperature, cooling, and alarms, but feeding still requires manual intervention. I enjoy feeding my fish whenever I can, and believe that fish benefit greatly from a diet that includes more than just flake food, but there are some good reasons for having an automatic feeder to supplement their diet. Many fish benefit from multiple small feedings throughout the day, rather a single heavy feeding, and an auto feeder can help with this. Also, I travel for work from time to time, and I don't always want to rely on a tank-sitter to keep my fish fed. Plus, I didn't want to have to hand feed every day, and become a slave to the tank. So an automatic feeder was on my list of necessities. But while there are many automatic fish food feeders on the market, almost none of them are easily integrated into a system with an Aquacontroller, so a DIY was required.
I chose the Eheim 3581 Automatic Feeder for this project based on its strong reputation and ease of modification. The stock Eheim feeder is programmable to drop food up to four different times a day, and also has a pushbutton which dispenses food when you push it. The DIY modification I'll describe below will take advantage of the manual pushbutton feature and use a signal from the Aquacontroller to trick the Eheim into thinking that the manual feed button has been pushed. The system design is simple. The Aquacontroller will tell one of our DC-8 outlets to turn on when we want to feed. A power supply is plugged in to the DC-8, providing safe 12 volt DC power to a relay circuit. The relay circuit will momentarily close when power is applied, then open and remain open. This ensures that food is only dispensed once even if it takes a minute for the Aquacontroller program to turn the DC-8 outlet back off. The heart of our DIY Eheim controller is a standard 12V automotive relay. When the relay is energized by the DC-8, it closes the internal switch connected to the Eheim. The Eheim thinks the manual feed button was pushed, and dispenses food. Meanwhile a charge is building up in the capacitor until it breaks the circuit, and the relay opens. The Eheim interprets this as you taking your finger off the manual feed button. The resistor slowly bleeds the charge off the capacitor, and in several minutes the relay will be ready to work again. Before that happens though, the Aquacontroller program turns the DC-8 outlet back off.
Modify the Eheim feeder
The first task is to attach wires to both sides of the Eheim's manual feed pushbutton. Remove the food hopper, battery cover, and AA batteries. Unscrew the 4 phillips screws on the bottom of the unit and separate the two halves of the feeder. Examine the circuit board where the LCD display and manual feed button are soldered in place. Drill two 1/16" holes in the circuit board near the switch, as shown in the photo below. Run a few inches of light gauge wire through the holes and solder one to each of the contacts of the mounted switch. If you were to replace the batteries and connect the bare ends of the two new wires, the electrical circuit will be completed just as if you had pushed the manual feed button, and the unit will rotate to dispense food.
Holes drilled in circuit board, and wires soldered to pushbutton terminals.
Next, drill a 1/4" hole and install a 2-contact, normally open (NO) audio jack. Solder the ends of the wires to the two jack terminals; it does not matter which wire goes to which terminal. But it is important to position the jack carefully so that it does not block the feeder's fan from moving. Reassemble the feeder and replace the batteries.
Rear view of the assembled feeder with audio jack
Create the relay assembly
Assemble the relay, capacitor, and resistor according to the diagram below and secure in a small plastic project box. The project box and its contents can be kept close to the 12V power supply, but I recommend using longer wires for the connection between the project box and the Eheim feeder's new audio jack. This keeps the relay further away from the heat and humidity of your aquarium. If you use a polarized capacitor like I did, you have to make sure the negative side is connected to the negative lead from the power supply. Also, check that the switched side of the relay (the side not connected to the 12VDC power supply) is an open circuit when there's no power flowing. If the feeder runs non-stop, you may have connected the relay to be normally closed.
Relay assembly schematic
Program the Aquacontroller
I like to turn off my return pump a couple of minutes before feeding to keep the food out of the overflow and give the fish first dibs. Anything they don't get to during the feed cycle is fair game for the refugium and frag tanks, which are further downstream. I use the following program to feed.
If Time > 14:00 Then PM1 OFF; return pump off
If Time > 14:02 Then FUD ON; dispenses food
If Time > 14:03 Then FUD OFF; ensures food does not continue to dispense
If Time > 14:15 Then PM1 ON; return pump on
Don't forget to test your new Eheim before you fill it up with food and stick it on your tank!
Eheim 3581 Automatic Feeder
1/8" Mono Panel-Mount Audio Jack (3-Pack) (Radioshack.com #274-251)
1/8" Mono Phone Plug (2-Pack) (Radioshack.com #274-286)
1000uF capacitor (Radioshack.com #272-1019)
10kOhm resistor (Radioshack.com #271-1126)
Project Enclosure (3"x2"x1") (Radioshack.com #270-1801)
12V automotive relay (Typical)
12VDC power supply
I've been using the Eheim automatic feeder for years now and have been very happy with the results. The modification detailed above is inexpensive and relatively easy for the DIYer, and I think it provides a significant upgrade in the device's capability.
Do ensure the Eheim is attached securely the tank rim or something sturdy to prevent it from falling into your tank. A WAMAS member suffered a tank crash when his auto feeder fell into his aquarium and the batteries rapidly dissolved in the saltwater, releasing whatever heavy metals they contain. It may also be worth noting that if you use X10 modules with your Aquacontroller, an Alarm/Relay module can be used to replace the relay circuit and power supply described in this project. I know the reef aquarist community opinion on X10 is mixed, but I've been using X10 modules with my display tank since 1997 and have found them to be flexible and reliable.
Finally, add a note below if you have any questions or comments. Enjoy!
Mysid Shrimp - are they in your tank?Often confused with larval offspring of many popular ornamental shrimp, some of the more interesting creatures that populate marine aquariums are from the order Mysidacea, the mysid shrimp. Much like other beneficial microfauna in our aquariums, they seem to spring up out of nowhere and represent a valuable natural food source for fish and invertebrates in our systems as well as occupying the important niche of helping to keep our systems clean.Without venturing into the debate of feeding freshwater food sources to marine animals, mysids are not as well known as their freshwater counterparts, mysis shrimp. Many companies harvest freshwater mysis shrimp and freeze them for sale to aquarists. They are a protein rich food and will help many finicky eaters to begin eating, hence their popularity. Mysids, however, are not typically sold as a frozen food and are available typically only through some of the larger mariculture facilities as live food. The ones that are typically available through these suppliers are larger than the ones commonly found in our aquariums, typically reaching sizes of up to an inch.On the other hand, the ones that we typically find in our aquariums seldom reach a size of more than 1/4" and are typically no larger than 1/8" or smaller. Often what we see are tiny silver streaks that dart back and forth in the dark recesses of our aquascaping, in tiny caves within our rock, in sumps, refugiums, and overflows, and wherever there are either no predators to eat them or there is sufficient cover to allow them to survive. While relatively transparent, they can be readily identified by the presence of two fairly sizable black eyes located at the tips of eye stalks that don't extend far past the carapace. Since the eyes are black and body is typically silver or clear, the eyes really stand out and are a telltale sign that you've got mysids.The compound eyes of the mysid shrimp are clearly visible here. Notice they do not protrude out far from the carapace and have relatively short eye stalks.Mysids are a typical shrimp in that they have a head and thorax that are fused together into one piece and then have a segmented abdomen or tail. Their body structure is the same as most shrimp that lack any prominent claws. Their telson (tail spike) is not especially long and in the ones typically found in our tanks the uropods (fan-like "fins" on the tip of the tail) are often longer than the telson.This picture shows the lack of any prominent claws used for predation or as a deterrent to predators.The head and thorax of the mysid shrimp are fused together into a single body part to which are attached the legs.Mysids have two body parts, a fused head and thorax and then the abdomen, or tail, seen here. The tip of the tail is where the telson and uropods are located. Notice the telson is shorter than the uropods.Where they tend to differ from the ornamental shrimp we put in our tanks is that they have an elongated body and their tails tend to be straight or sometimes even curve upwards instead of curving down in my experience. The typical ornamental shrimp is a benthic organism that spends much of its time walking around on its feet, scooting backwards to avoid predation and conflict. Mysid shrimp, though, are more similar to pelagic shrimp like krill except that they don't jet backwards but scoot forward to escape. They are constantly on the move and rarely settle down to the bottom for more than a few moments. Despite this resemblance, the ones we have in our tanks are in fact benthic although there are also pelagic species out there.The tail of this mysid curves up towards the telson, different from the typical downward curve of the tails of typical benthic ornamental shrimp.Notice the legs that are swept forward - in some species they use these abundant legs to collect detritus or other food particles which are then swept from the legs to the mouth.This female mysid shrimp is carrying embryos in its brood pouch, or marsupium, hence the common name opossum shrimp. When mature, the juveniles will be released and then new eggs will take their place.Mysids consume a wide variety of foods and typically the varieties we see in our systems are consuming algae, detritus, and capturing microfauna smaller than them. As omnivores and detrivores, they help to keep our tanks healthy and maintain a good balance in our closed systems. Typically, once established, they are present in far greater numbers than are seen. The young are as small as many of the pods we often see (or don't see!) in our systems and hide as they are often eaten by their parents.So, next time you see a tiny silvery flash darting back and forth as you sit in front of your tank shining a flashlight into cracks and crevices in the rockwork (and you know we all do that!), chances are you've spotted a mysid shrimp!Click on the thumbnail to see the full body of the mysid shrimp from above.Click on the thumbnail above to see how the mysid moves forward instead of curling its tail to escape backwards.Click on the thumbnail above to see how the mysid's legs help it to swim forward instead of walking around or scuttling backwards as typical ornamental shrimp do.
The Great Tank BurstPoorly constructed homemade tanks or tanks not placed on a level surface, when filled with water, will put undue stress on the joints and seals causing a burst. Also, the seals in some very old tanks can weaken. More than one aquarist has had to deal with a hundred gallons of salt water in their living room. Consider that one gallon of water weighs 8.5 pounds (2.2 liters weigh 1 kilogram).Prevention: Buy from quality tank manufacturers! There are too many cheaply made tanks on the market. Test used tanks by filling them with tap water, drying the outside and let them sit for several days. If possible weigh all live rock, sand and equipment before putting it in the tank. Know the total weight and ensure your stand will support it. Do the math! Make sure your tank is level and sitting on a completely flat surface! Do not trust standard manufacturer stands in an earthquake zone. Thick steel stands or stacked cinder blocks will be quite sturdy. Attach a nice piece of panel or wood to the front and sides if the cinder block looks too unsightly.AvalanchesRock is often stacked in dangerous ways in a tank. What many aquarists don't realize is that sand slowly dissolves causing even the most carefully stacked rock to come tumbling down and crack or bust the glass. Long before sand dissolves, livestock can burrow in the sand under the rock and cause an avalanche. Some livestock, such as octopuses, are very strong and can easily shift rock around causing an avalanche. True Tale of horror: One aquarist heard a loud crash followed by a wave of water as he lay in bed at 3am in the morning. A large rock had tumbled down and smashed through the front glass of the tank. The tank emptied in only a few seconds. The salt water hit electrical cords and surge protectors and destroyed his TV and other electrical appliances. His living room had substantial damage mostly to carpets and furniture. All this caused by 80 gallons of salt water.Prevention: Place rock gently on the bottom of the tank
We have all heard the stories. We at WAMAS Waves have told them in our last three issues of the Marine Disasters series. Tank catastrophes caused by a myriad of problems that led to the loss of thousands of dollars livestock, damage to equipment, damage to our homes, hits to our pride, and hasty exits from the hobby. It is a risk that we accept in order to have these serene creatures, vivid colors, and part of the ocean in our homes. Right? Wrong.Errors are a part of every human endeavor. We all make them every day. However, when you anticipate the consequences of those errors and make considerations regarding the outcome, you can greatly reduce or eliminate problems resulting from those errors and associated heartache. This quarter in the Mixed Reef, I am going to share my system design philosophy that has been forged by 23+ years of marine experience and tempered by my work as a nuclear safety and reliability engineer. This philosophy is a concept that I like to call the "dual failure reliability criterion." What does that mean? It means the system is protected after any one failure and it would take two failures before a problem becomes an issue.Protecting your reef and all you have put into it requires a little time, effort, and sometimes money. But with all of the time, effort, and sometimes a lot of money you have put into it. The expense is worthwhile.Now, how do you go about applying the dual failure reliability criterion to your reef? By asking questions: "What can fail?" "How can it fail?" "What happens if it fails?" "How likely is it to fail?" "What can prevent its failure?" and "What can prevent or mitigate the consequences of its failure?" Do this for each part you add to your system and you will surely identify things you can do that will make big improvements to your system resilience.With that, let's talk through a few examples.Starting simple: What can fail? The heater. When asking "What can fail?" the answer is always an object, rather than an action. Thinking about glass breaking, seals leaking, or overflows clogging focuses your actions more than addressing the end result of water on the floor.How can it fail? On. Off. Leaches chemicals into the water. Adds a voltage to the water. Start by avoiding the cause of the failure (case breaks and then leaches chemicals into the water) and focus on the failure itself. Once you are satisfied that you have identified how the part can fail, add paths to reach that failure. On