Solar Hot Water Heater for Fish Tanks

OK...so I got the great idea of building a solar hot water heater out of black poly tubing and having that connected to one of my fish tanks in order to cut the electric bill down on the aquarium heaters I run. I am having mixed results, with a net gain of 4-5 degrees over the ambient temperature of the fish tank water. I was expecting much more.

Initially, I placed 75ft of poly tubing into a 4'x4' box (2x4's) made out of Dow blue board and clear / white poly carbonate panels with the inside painted black as shown in the video.  This is all connected to an Aquatop 496 GPH submersible pump which has been choked down to about 250 GPH to give the water enough transit time through the pipe to heat up. I found that I did not have enough pipe so I added another 100' to the existing pipe, I am in the process of sealing the box, and I will need to use glass on the front to better trap the heat as the poly panels don't do a good job. I have a resource to buy cheap used windows and will be heading down to look for one soon.  I have posted some pics of the unit as well.

 Until next time....

Water Quality Test for each system

I received my API Freshwater Test Kit a couple of weeks ago, and was able to test the nitrogen cycle of both tanks in relation to each units biological activity. 

After running both Aquaponic tank systems for approx. 2 weeks without media in the growbeds, and another week with media, while having approx. 10 gold fish present in each tank for the entire duration I was able to see where my tanks ammonia, PH, Nitrite, & Nitrate levels were at in the cycle.

On October 8th, I had the following results tested at 80 degree water temperature.

Tank System 1:
PH: 8.8 PPM
NO2: 5.0 PPM
NO3: 10 PPM
NH3/4:  .25 PPM

Tank System 2:
PH: 8.8 PPM
NO2: 5.0 PPM
NO3: 10-20 PPM
NH3/4:  0 PPM


Another test was performed on October 15 with the following resutls tested at 76 degrees for water temperature.

Tank System 1:
PH: 8.4 PPM
NO2: 0 PPM
NO3: 20 PPM
NH3/4: 0 PPM

Tank System 2
PH: 8.4 PPM
NO2: 2.0 PPM
NO3: 20 PPM
NH3/4: 0 PPM

As can be seen the tank systems are for the most part cycled, with the exception of the PH. which is high and is causing PH block for some of the nutrients in the system such as Iron, Calcium, & Potassium. A good organic pond fertilizer containing 10% iron, and Phosphate only was added to each tank to mitigate the iron deficiency, but due to the PH block this did not help.

I had added over several hours approx. 1/4 Gallon Muriatic acid to each system which temporarily lowered the PH to 7.8, after waiting 24 hours the systems were retested and due to the buffering action of the expanded shale, the PH crept back up to 8.4. I will continue to monitor all water quality on a weekly basis until the systems are stable, Muriatic Acid will continue to be added until I can get the PH down to 7.8, after which I will let it digress on it's own.  More plants were added, some of which have shown signs of iron deficiency. I have an organic powdered chelated iron product ordered which should arrive sometime this week. I will add this to the systems and report back on the results.

Overall, plant growth has been outstanding, I have one Stevia plant which has added about 12" of growth in two weeks, and an Early Bird Tomato plant which has added approx. 6-8 inches of growth along with blooms in the same time frame.  Kale has doubled in size, and herbs have had significant growth as well. Pepper plants are putting on more fruit as well.

More to follow.

Greenhouse Re-design with Electrical and Water sources added.

OK...so the first go around on the greenhouse was pretty good, but after completing the structure and closing the door, with the door insert window open of course, the temperature soared to a whopping 135 degrees inside the greenhouse....not good for man or greens. So back to the drawing board, and after several hours of research I discovered that while I had approx 12 sqft of ventilation, I really needed at least 10 percent on the sides of the building and 15 percent at the ridge based on the square footage of the greenhouse which is approximately 240 square feet. While the 500 CFM solar attic fan took care of the ridge requirement  the three 4 sq ft windows in the side walls were not adequate for cross ventilation, so I was off to make some adjustments...major ones. I had to remove a total of 6 PVC panels on the south facing side of the building and turn them into windows as seen below. This provided another 24 sq ft of ventilation.

 

After further testing, this only reduced the temp in the greenhouse by about 10-15 degrees, still not enough, so the next step was to cut two openings in the north facing wall to allow for more airflow across the greenhouse. These openings were turned into shutters rather than windows for protection against northern winter winds and will be insulated as time permits, both openings were cut out to approximately 2ft x 4ft, for another 16 sq ft of ventilation. This dropped the inside temp to the ambient outside temp when all ventilation was opened. I also fitted barrel bolts to all openings in order to secure them when closed....here is a pic of the north side of the greenhouse.

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House screening was placed on all openings for pest control. Next I was off to run the electric to the building, this of course took me a couple of days to complete.I have 4 -110v 20A outlets, three inside the building and one outside the building as shown above and below.

A photo of the florescent light I installed.

I also had to dig an 8inch deep 60ft trench and place 12-2 UGF wiring to the building which took the longest...especially in the 100+ degree heat...whew!!! was it hot. Next came the water line, where I dug a 2ft deep trench 35ft to the house in order to tie into the backyard faucet. I placed 3 hose bibbs inside the the greenhouse for convenience with two being on stand pipes (see photo above) and the third being at ground level so I can drain the water out of the system when needed for repair or due to freezing temps in the winter.

Well, that's pretty much it for this post...now that the greenhouse is complete I can move on to the next phase building my aeroponics/aquaponics systems...more on that in the next post.