Jacob’s Blog

I came across these on the web somewhere… good for a chuckle.

see more crazy cat pics

This is a side-track from the usual “Project 360″ post. I just wanted to share a little about a spreadsheet that I developed for modeling a piping system and determining the optimum pump to use. This is a very useful tool for designing a new process line and understanding the system curve (flow vs. pressure drop in the system). The program is driven by Excel and custom written Visual Basic routines. The limitations of this system are:

- Calculations are for Newtonian Fluids only (in a nutshell a fluid who’s viscosity is independent of shear forces)
- Pump suggestions are limited to those in the database of the program (which can be expanded upon as time allows)

Step 1: Enter the Process Specifications
These specs influence pressure losses and/or factor into the pump operating requirements. Note that several different pipe and tube types are available to choose from. These affect the physical sizes and friction coefficients used to determine velocities and frictional losses through the system.

Step 2: Enter the Inlet Conditions
The inlet conditions include static head (or lift) of liquid, pressure (or vaccum) on the liquid, and all of the fittings, valves, and other contributors to frictional losses. Note that there are a variety of fittings and valves to choose from in sizes from 1 to 6 inch. I’ve graphically scrunced the screen down, usually there are about 12 options for different fittings and about the same for valves. After the inlet model is complete, the pump suction head or suction lift is given.

Step 3: Enter the Outlet Conditions
The method of entering the outlet conditions is very similar to that of the inlet conditions. After the outlet model is complete, the pump discharge head is given.

Step 4: Suggest Pumps
Pump suggestions are based on the target flow rate, the total system head (net inlet and outlet conditions), and the net positive suction head available as determined by the system model. The database is mined and the for pumps that produce the desired flow (within a pre-defined tolerance) at the system head pressure. Multiple pump matches may be returned if they are found to be suitable. To analyze the actual flow of a given pump in the system the analysis option can be used. This will calculate the intersection of the system curve and the pump curve exactly.

The desired pump can finally be plotted against the system curve for documentation purposes. Hyperlinks to the manufacturers pump curves are also included for each pump as a double check, or to look at other impeller and/or motor sizes (for those “hobbyists” reading this you are probably not accustomed to seeing multiple impeller or motor sizes for a pump housing - this is more common in commercial applications).

In this case I have modeled the piping on my 360g aquarium from my sump back to the display tank. As you can see a Sequence Snapper was the pump best suited to do the job (I actually listed the pump as a Dart, and the Snapper as the impeller size, since they are the same other than having a smaller impeller). This is a very low head / low flow application and all of the other pumps in my database are commercial pumps ranging from 3/4 HP to 60 HP, thus no other potential matches.

I use this program frequently when designing new process lines, or modifying process lines. This utility has also been helpful to troubleshoot problematic pipe systems. By modeling the exact pipeline and existing pump I can determine what the flow and pressure should be, these figures can be compared to the actual measured values to better understand if the lines are being fouled or restricted unexpectedly. I developed a similar calculator for power-law fluids which are non-newtonian, these calculations can become more complex and rheology testing must be done on the fluid before any calculations can be performed.

I hope this has been interesting, on some level, to those of you reading. I’m always happy to run calculations on a system for anyone who needs a hand, just drop me a line. Thanks again for visiting, until next time….

Jacob.

Not much progress to report on the tank, “real work” and other projects at home have been keeping me busy. I did change my mind on the lighting setup. I was planning on running all T5’s but decided to go with halides at the last minute. My bulb choice was the Iwasaki 175w 15k. I’m running them on the new model Icecap 175w electronic ballasts. The spectral data and PAR numbers can be found on Sanjay Joshi’s site here.

As for reflectors I’m running Lumenarc III’s. Some comparisons between these reflectors and others can be found in this article by Sanjay Joshi. I’m sure there is more current data on these but I couldn’t dig it up.

Based upon my knowledge of all the halide bulbs and ballasts tested (by Sanjay) to date this combination provides the best efficiency possible. The PAR produced is more than many 250w halides can produce. The only drawback is that the lighting is very white (this is a plus if you prefer white light). Most likely I’ll still supplement with some blue T5’s, or possibly try a different (more blue) halide bulb, such as the AB 13k, or Coralvue 12k (both of these lamps produce less PAR then the Iwasaki’s however).

I felt that the depth of the tank will be too much for the T5’s to penetrate effectively. I want to keep my aquascape low (leaving plenty of swimming room for the fish) so this became an important factor in the decision.

I’m in the planning stages of the stand and canopy now so hopefully I’ll have an update on those soon!

Happy New Year!

It’s been busy around the office lately; between the holidays and everyone wanting to deplete their ‘07 budgets I havevn’t been able to do more than think about the tank project lately. Today a friend came over to help me run some of the piping. With his help I managed to get the water lines and electrical conduits run from the office closet to the water room.

Let me just say, working in a small crawl space, on the dirt, sprawled out on chunks of concrete remnants and other odds and ends is not my idea of a good time… and I have to go back down there at least a couple more times (to finish gluing and to run ducting).

Here are a couple of pics of what we got done today, at least what was done above the floor, no shots from the crawlspace - the less I see of it the better!

In the closet

Here’s the other side of the wall next to the tank stand.

From top to bottom: high voltage, low voltage, water out, water in.

Not much to show for a lot of work, but I’m pleased with the forward progress. I recently placed an order for the bulk of my lighting needs and other odds and ends that just about completes the necessary equipment. From a top level perspective here is what’s left to do:

1. Complete the piping shown above (mostly gluing)
2. Run the ducting for air exchange
3. Complete the sump (add baffles, bulkheads, etc…)
4. Hard pipe the sump, tank, return pump, peripheral equipment
5. Hard pipe the water room and tie it into the tank piping
6. Complete the stand (new skin)
7. Build a new canopy
8. Build the electrical panel
9. Install and wire the electrical panel to all equipment
10. Start this baby up!

I was hoping to be done by the end of February, but unless I get some serious help I can see there’s no way that’s going to happen. Well, I have some real work to finish up now, so until next time…

I need some fresh air!

Salt water aquariums tend to evaporate water quickly due to the constant water movement, warm water temperature, and large surface area exposed to the air. In my experience it’s not unusual to evaporate 1-2% of the total water volume per day.

My system will be about 400 gallons total water volume including the sump) which equates to about 6 gallons of evaporation every day. That’s over 2100 gallons a year of evaporated water. In order to remove all the moist air I decided to build an air exchange system. It’s fairly simple:

1. Make the stand and canopy as air tight as possible.
2. Using ducting create an loop from outside the house, through the stand and canopy, and back out of the house.
3. On the outlet side of the loop install an inline fan to pull fresh air through the loop.

A rule of thumb for residential ventilation is 15x the room volume per hour - minimum. I’m not moving the air contents of the room, but rather the air volume of the stand and canopy which is about 100 cubic feet. The bare minimum turnover is 1500 CFH, that’s only about 25 CFM. Since I know I won’t be able to get perfect seals on the stand and canopy, and I don’t want to take any chances with the system being inadequate I’m going to shoot for about 100 CFM, once per minute.

If air velocity becomes to high noise may become an issue, and the last thing I need to is to have a vacuum cleaner sound in my office all day long! 15 feet per second is on the upper end of ‘acceptable’ for a typical office (building). In a 4″ duct it works out to about 80 CFM, which is a little less than I was shooting for but it should be fine for the application.

Next, to size the fan, the pressure drop due to friction needs to be calculated. In case anyone reading is interested the equation is:

Δp = (0.109136 q^1.9) / d_e^5.02

Δp = Pressure Drop (inches of water) per 100 feet of ducting
q = Air flow (CFM)
d_e = Duct Diameter (inches)

The design requires about 30 feet of 4″ ducting, and 30 feet of 6″ ducting (the flexible type, which has a friction factor close to 4″ smooth duct). There are also (7) 4″ elbows, and (2) 4″ tees, which are equivalent to about 4 feet of ducting each. That’s a total of approximately 100 feet of duct. Put it all together and it works out to about .65″ of water pressure loss.

Based on reputation and ability to handle to moisture and wet environments I went with a thermoplastic inline fan by Fantech.

Fantech FR-140

Based on the data below I decided the model 140 was most appropriate.

Sizing Charts

It would appear that the model 110 is a better choice, but it’s not Energy Star compliant and actually uses more power than the model 140 (60w max). I’ll end up putting an iris plate in the duct to restrict the air flow to around 80 CFM. I purchased the fan and have it now; hooking it up to my Kill-A-Watt reveals that it is in spec and, just like a centrifugal pump, when restricted it actually draws less power. It’ll most likely be drawing 40-45 watts and I’ll be running it 18 hours a day.

There are multiple benefits to running an air exchange system such as this. Not only do I remove the moisture laden air, but the constant air movement over the tank will increase evaporation, and keep it running cool. In addition to that the air inlet is coming from under the house where the air is cool and dry. Even in the winter months when the house is closed up the tank will be getting a constant dose of fresh air which should prevent the typical seasonal Ph swing.

Now if I can only find some time to stop typing, and start installing….

Jacob.

Pushing Forward

It’s been too long since I’ve updated so here’s the latest. When setting up an aquarium in your office it does help to actually have the tank IN the office… not outside next to the garage. With the help of some friends the tank is now inside! Prior to moving it in I spent 2 weekends polishing out the scuffs and scratches from the previous 6 years that the tank was set up. I used a Micromesh HP-100 kit. This is a hand sanding process that takes a lot of time, I don’t think I’ll ever do it again (at least not on a large tank) but the results are to my liking.

Tank In The Office

I’m planning to fabricate a new skin for the outside of the stand, that will be one of the last steps of the project (long way off).

With the tank inside I wanted to focus my attention to the plumbing and ventilation. Below is a list of all of the individual runs that need to be made between the tank and the remote water room.

Run 1 - Water Out
To accomplish automatic water changes this line will be connected between the house drain line and a 3-way actuated ball valve located just downstream of the return pump. When the valve shifts water will be pumped from the sump to drain.

Run 2 - Water In
To accomplish automatic water changes this line will be connected between the pump in the water room and the sump to replace water that was previously pumped to drain.

Run 3 - Low Voltage
All of the 24 volt DC communication to and from the PLC will be carried in this run. The equipment at the tank will be controlled via solid state relays and a power center. The equipment in the water room will be controlled by a similar power center located there. This run will also carry (2) 1/4″ polyflow tubes for top off and dosing from the peristaltic pump in the water room.

Run 4 - High Voltage
This is a single 120 volt AC line to power the air exchange fan which will be mounted under the house. It will be tied into the power center at the tank. The water room has 120 volt power so there’s no need to run another line.

Run 5 - Air Out
This is a 4″ galvanized duct for air exchange, which I’ll talk about further below.

Run 6 - Air In
Ditto above.

Since this was going to require cutting multiple holes in walls and floor I wanted to get it right. Here are a couple of pictures of the model that I made to lay everything out. I cut the walls and floor down and made them transparent for better visibility.

I’m running everything in/out the back of the tank and into the wall which happens to be a closet. From there I’m going through the floor and into the crawlspace… I’m not looking forward to installing all the lines in the crawlspace!

I started drilling some holes recently, here are some pictures:

This is where I’m at now. I’m contemplating my next move, or possibly putting off crawling under my house to run a bunch of pipes and ducting! Although I haven’t installed it yet the next blog post will be all about the air exchange system - so make sure not to miss it!

Jacob.

The Water Room!

It’s been awhile since my last update. I’ve been wrapped up with work, but also with getting the water room together. This room is actually more like a built in storage area on the side of our house, it was the result of an addition. When complete, the water room will hold (2) 65 gallon drums, (4) 5 gallon totes, a 55 gallon quarantine tank, my RO/DI filtration system, and several pumps. Plumbing will run from the water room, under the house, and up through the floor to the display tank (this is not installed as of today).

Here are a few pictures of what I’ve been working on. I should have taken one when the room was just bare frame work and full or yard tools, but it was pretty scary and I didn’t want to frighten anyone!

Drywall just up

Textured and painted with support frame

Drums and Quarantine Tank in place

The Quarantine tank is going to be very important in the success of the new aquarium. All new arrivals (fish and coral) will spend at least 2 weeks in here. I have an AquaC Remora hang-on skimmer, 2x 24w T5 lighting, a Hydor Koralia for water movement, and an Eheim auto feeder. I had to add a notch in the side of the tank in order to get the skimmer on.

Newly added notch to fit skimmer on tank

The 65g drums are HDPE food grade drums that a client of mine let me have. These are great drums, they’re very sturdy, completely sanitary, and they even have a level marker on the side that reads in gallons. They had organic rice syrup in them, a good rinse with the hose and they cleaned right up. I did cut a square opening in each of them to allow access.

Notch in Drum

Modified Cap with connection for RO/DI water.

The drum on top will store RO/DI water. The level will be automatically maintained by a high and low level sensor which the PLC will use to determine when to open the RO/DI soleniod valve for filling, and close when full. The drum on the bottom is saltwater which will be mixed manually by me. This drum will just have a low level that will trigger an alarm on the HMI screen to let me know when I need to go mix up more saltwater. Automatic water changes will be executed by a Gorman Rupp 14521 pump located next to the lower drum and scheduled for 15 gallons once per week.

I’m also putting together an automatic top off system of diluted 2-part supplement. The system will automatically recharge when empty and alert me when more 2-part needs to be added to the concentrate tanks. I’ll go over the details of the auto water change and auto dosing/top-off system on an upcoming thread.

That’s all for now, pretty soon it’ll be time to move the big tank into the house, things are getting exciting!

(you can see all of the Project 360 blog posts here)

Aquarium Lighting

So far most of the decisions in this project have been tough ones to make, lighting was definitely no exception! My current tank setup uses T5 high output fluorescent lighting. The only lighting more efficient right now is LED, which is very new technology, and very costly. Although I did consider metal halide lighting I recently settled on an 8×39w T5 setup by Icecap. Under normal circumstances the lamps are 39 watts each but the Icecap ballasts really get them cooking at 60w each. The Icecap reflectors are among the best made right now, making this a powerful and very efficient setup. Below is a drawing, looking down on the top of the tank, that shows the layout I’m planning to use (click image for more detailed view).

Lighting Arrangement (Click for detailed image)

The openings on the top of the tank are 23″ x 20″, the middle opening is turned on its side because of the overflow at the back center of the tank. Even though the lights are on 6″ centers they should put out plenty of bright light for soft corals and fish. The lights are roughly 8″ off each end of the tank, and 6″ from the front and back. This is fine since I won’t have any rock/corals in these areas anyway, and there should be plenty of reflected light to prevent any dark areas.

Other Options I Considered

The only other strong contender would have been (3) 175w Iwasaki 15k metal halide lamps running on Icecap electronic ballasts and using Lumenarc III reflectors. This is one of the most efficient metal halide setup’s available - putting out as much, or more, photosynthetically available radiation (PAR) as many 250w halide lamps. Here is a spectral plot executed by Sanjay Joshi. I have no doubt that I would have been able to keep stony corals under this lighting, as well as all other types. So why not go for it? It came down to the fact that these lamps are extremely white in appearance. I prefer a slightly blue appearance and I know I would have need some blue supplements. This would have meant more electricity usage and more upfront cost. I’ll always wonder how I would have liked the Iwasaki’s, but I know I’ll be happy with the T5’s.

Well, until next time!…

(you can see all of the Project 360 blog posts here)

The Skimmer

Choosing a protein skimmer for this system has probably been the most difficult decision to date. Knowing that this tank is going to be swarming with fish who are constantly eating and pooping, and the skimmer is the primary means for removal of these organics, I realized that I’d need a “good” skimmer. The downside to good skimmers is A) they come with a big price tag and B) they’re primary energy consumers since they run 24/7. So how do you quantify what a “good” skimmer is?

Skimmers do what they do through a process called foam fractionation. All of the micobubbles in the skimmer body carry an electrical charge that they gain through friction (have you ever rubbed a balloon on your head and made your hair stick up, or stuck it to the ceiling?… same idea).

The charged air bubbles attract oragnic molecules in the water and carry them up to the top of the skimmer where they form a foam column. The foam overflows into the collection cup where you get rid of it. Ok some of you already know this! Where am I headed here… ah - the air! Ideally a good skimmer would have about a 50/50 air water mix. This is tough for most pumps though since centrifugal pumps don’t like to pump air, so we usually settle for less air and more water, fine! Bubble size is important too, the smaller the better. Taking into account the air flow, water flow, and power consumption the theoretical performance of a skimmer can be quantified. The physical design is important too, for instance the bubbles need to break in the neck of the skimmer, not below in the transition area.

Taking all of the above boring information into account I looked at several options before settling on the Tunze 9420. This is one of the newer style Tunze skimmers (in fact only a few have shipped to the U.S. as of today).

Tunze Master DOC 9420

With this skimmer being so new, and not proven, I’m going out on a limb. This is an in-sump needlewheel skimmer. The specs are 1300 lph (~350 gph) 800 lph (~210 gph) of air at 23 watts. This amounts to 34 lph / watt, which is a great efficiency. It’s rated for 528g (fish only). Tunze has a rating system that downgrades the skimmer rating based on the type of tank inhabitants. On a soft coral dominated tank it rates at 20% less (422g), on an LPS tank it rates at 316g, and on an SPS tank it rates at 212g. Tunze rates all of their skimmers on this system.

The skimmer design is a little different than a typical needle wheel; the neck opens into an intermediate chamber, which then opens into the collection cup. I don’t yet know how this design improves skimming, but it does prevent over-foaming of the collection cup. One of the nice features of this skimmer is that it is already plumbed for a second pump, which effectively doubles the capacity. Once I get running I’ll report back actual results!

Other Options I Considered

I first considered buying an AquaEuroUSA model 400. The upfront cost is very reasonable, but the pumps would have needed replacement. They’re not very efficient - and, as many people later found out, poorly made! The next option would have been an H&S A200. In my opinion H&S is the most well built skimmer on the market, better than Deltec, and for a little less cash. I decided against the H&S because it uses almost 3 times the energy as the Tunze does, with about a 40% increase in air and water throughput, not to mention it would have cost more. Even if the Tunze doesn’t perform as well as I’m hoping, I can add the 2nd pump to it and still be under 50w. All in all I’m excited about the Tunze, we’ll see how it goes!

The Runner Up’s

Stay tuned for more…
- Jacob

(you can see all of the Project 360 blog posts here)

The Return Pump

As usual energy efficiency was a big factor in making a decision on my return pump. I already have a brand new Gorman Rupp model 14520 - which is a great pump, but not very efficient (over 2 amps!) Aside from energy efficiency I wanted between 700 and 1000 GPH moving through the sump. The protein skimmer that I selected (more to come on this later) could pull as much as 700 gph of water flow so I wanted to at least hit this mark. I also factored in some extra flow to run through a fluidized reactor. At the end of the day I decided on a Snapper by Sequence.

Snapper Reeflo Pump

That’s actually a Sequence Dart pictured above. The Dart and the Snapper are the same pump. The only difference is that the Snapper has a smaller impeller which decreases its capacity and likewise decreases its power consumption. Most centrifugal pumps follow this rule: the less water they’re moving, the less energy they’re consuming. Some of these small hobby pumps follow that rule, some follow it to an extent. My guess is that these pumps are running at such low pressures that their power consumption is inconsistent with flow as the pressure approaches zero. It’s only a theory, but that’s neither here nor there.

Getting back to the point; I picked up the Dart, used, as a backup pump. The Snapper is new in the box and I really didn’t want to unpack it just to get a picture for the blog!

Snapper Pump Curve: At about 8′ of head the Snapper produces around 1400 GPH @ ~95 watts.

Dart Pump Curve: At about 8′ of head the Dart produces around 1900 GPH @ ~155 watts.

As you can see from the curves above the Snapper is more than enough pump for my needs. I can hook tee off to a couple of fluid beds and still have flow to spare. Most likely I’ll be throttling it back a little, which will also help save on energy.

Other Options I Considered

In this case I looked around - a lot - but didn’t really see any viable choices other than the Dart. Some of the brands I browsed were Iwaki, GenX, Posiedon, Eheim, and Gorman Rupp. Most of the other pumps in the flow range I was looking for were energy hogs. Those that weren’t just didn’t put out the flow that this system will require. I also compared efficiency of all of the pumps I considered and nothing beat the Sequence pumps in that department (To be fair Tunze does have some super efficient centrifugal pumps, just way too much flow for this system).

Stay tuned for more…
- Jacob

(you can see all of the Project 360 blog posts here)