Backyard Aquaponics
A place to discuss aquaponics

Hello, I am new to the board and am trying my first test aquaponics system and had a question for you guys. I am sorry, I don't have pictures yet.

I have two plastic bins (probably about 20 gallons each) I am using, one for the fish and the other with a gravel bed, the gravel bed is above the plastic bin for the fish. I am using the flood and drain method, I am really broke right now so I am trying to just use what I had available, the pump I am using is just a small one from a desktop waterfall project I had awhile back, it uses a 3/8" tube, the siphon tube is 1". I just put a hole towards the top of my gravel bin and have the siphon tube in there like an upside down "U" and I sealed it in.

The problem I am having is that the siphon will work flawlessly for like 8 hours and then just stop working correctly, when it stops working the water will get up to the top of the siphon and then start draining it as fast as the pump is pumping the water in, but it won't pull a full siphon and drain the bin. I am wondering if I have too big of a siphon hose or something like that.

Also another small question, right now I have the pump running all the time, but I would like to try and get a timer to run it like 15 minutes every hour like I see alot of people doing here, my question is, how do you make sure when the pump turns off that it isn't right before the grow bed was supposed to siphon and leave the grow bed waterlogged for the next hour?

Thank You.

Welcome M!

It may help to make a little dip at the outlet of the loop, to trap a little bit of water at the end of the loop. This can help the siphon avoid the problem of trickling but not starting. Some have used tilted elbows for this, maybe try just bending the loop a bit at the end to hold a dab of water in there.

To make sure the bed doesn't stay full just put a little hole in it to drain it if that happens.

I've had a similar problem with micro sized systems. I've found that the tiny little pumps are often just barley able to manage a little siphon. When running right on that line I found that just a tiny bit of gunk will slow the pump down enough that it is no longer able to kick the siphon over.

Tell us what happens if you were to turn off the pump for a moment and then turn it back on? Is it able to kick the siphon over when you do that?

I have my aquarium system running on a timer so that it does shut off and come back on. This seems to back flush the gunk out of the pump so that the pump stays clean enough to kick over the siphon.

Since my aquarium system has such a small fish tank, I've been running the pump with a 15 min on 15 min off cycle much of the time, even if for some reason the siphon got out of sync with the pump timing, it doesn't leaves the beds flooded for too long and I'm generally only growing lettuce and house plants in there so they are not so picky about wet feet anyway.

Another option might be to try adding some sort of slight restriction at the bottom of your siphon tube or as some people have done, place the bottom of the siphon tube in a little container of water you could hang at the right level. However, this might make starting the siphon proper (without the trickle over effect) better but it may also cause trouble with getting the siphon to stop properly and then require a breather tube or something.

Thank you very much for the replies!

I am going to try adding a dip to the outlet of the loop as suggested and see how that helps it, that makes sense on how it could work. I would be surprised if it was junk in the pump as I just setup this system and have no fish or plants in it yet, just the gravel bed and water tank, the water is almost perfectly clear at the moment. I was planning on running it for a week like that before I added the fish to make sure I had stuff running right and hopefully to let the chem from my city water try and evaporate.

I am doing this tiny system just to learn some of the basics, I am planning on building a 10' x 16' greenhouse in the spring that will be totally aquaponics, I just got 250 2'x2' pieces of glass from an old greenhouse for free that I can use for my greenhouse. I am working on collecting the other components throughout the winter here, by monitoring craigslist.com I am being able to pickup pretty much everthing I will need for free.

Good luck with it all.

Starting a test system is definitely a good idea so you can learn and practice.

Can I recommend looking into fishless cycling before you add fish in there. With such a small system it doesn't give you a lot of leeway when you have fish in there so getting a population of bacteria going before you add fish can save a lot of stress.

And here is to getting the siphon working properly before adding anything else to the system!

Thanks for the mention of fishless cycling, hadn't read about that yet, just did a quick search on the board though and found out about it, I will give it a try if I can find the urea and maxicrop locally here.

For this small system I am just planning on using some cheap goldfish, so if I lose some it won't be a big loss, but I was a bit worried about getting the bacteria going.

If you know someone with an established aquarium just get a good handful of the gunk from their filter and that will get you going good.

I cycled with (pure household) ammonia in two weeks, but it was a long trip to find a store that had it. If the bottle foams when shaken or smells like pine then it's a no-go, detergents will kill the fish.

Just wanted to post a quick reply, been a couple weeks and I have been pretty busy.

I made the changes to the siphon by adding two 90 degree bends to bring the end up and that worked like a charm for starting the siphon, however like someone mentioned above one it started it wouldn't stop the siphon. If I turned off the pump for a few seconds it would break the siphon and then when I plugged the pump back in it would cycle again one time, etc.

So since I didn't want this to run 24/7 anyways and I have another side interest in robotics/programmable microcontrollers I just hooked up a relay to my pump and programmed it to leave the pump on for 15 minutes and off for 45 minutes, I know there are timers that will do the same thing but I had the stuff for this and it cost me a $3 relay.

So I am getting some slime from a friends aquarium this weekend and am going to be putting 3 tiny goldfish in to hopefully start getting this system cycled. I will be starting a thread for this system and posting pics in the next couple days, its not much of a system but I thought I would at least document it.

Thanks for the update! Good luck with the new system!

Can you add a breather tube to the siphon?

Yes I could have added a breather tube as was suggested, but since I didn't want the pump to run all the time anyways turning the pump off electronically fixed the issue, so rather than messing with the breather tube I just put the electronics in place earlier than planned.

As a side note, I have been planning on incorporating my electronics into my aquaponics system to monitor the air & water temperatures, ph levels, light levels, etc. And hopefully add in systems that would turn on grow lights automatically if the light level are too low during the day, or turning on aquarium or electric space heaters if the air or water gets to cold. As I mentioned before, this is just a very small test for me to learn the basics, I am planning on building a decent sized system in the spring that I would run year around in a greenhouse I am currently planning.