Backyard Aquaponics
A place to discuss aquaponics

hey mike

yeah i increased the pipe size to 40mm and now I dont have to wind the pump back so much.

Plant growth is not amazing as i dont think i have enough fish to drive the system, i only have 5 medium goldfish and 4 small goldfish in a 700L tank. i only have half as much volume in grow beds (360L) compared to fish tank so im wondering if im cycling water enough. Some people on the forum are cycling the equivalent of their whole fish tank volume every hour. Im probably only doing around one quarter every hour. My water was green initially, seemed to cycle after a few weeks and get clear but now has gone green again with all our hot weather lately. Nitrates, Ammonia and nitrites are all reading zero and the plants dont look that green. im hoping to get some silver perch in the next few weeks. Ive called the place in Gidgegannup but there is a 3 week wait.

My grow beds are really small and shallow so the one outlet seems fine though i am having some troubles making sure the grow beds fill to the top since my sump tank is only 220L. It takes about 120L to fill both grow beds but with my standpipe arrangement (standpipe with holes) im getting drainage as its filling so im thinking of changing my drainage system over to a bell siphon or auto siphon. trying to read and learn as much as i can about these before i make a few more mistakes! do you have to have a u bend to make these work?

im growing kang kong and water chestnuts in the pond aswell. i will post some photos.

looking forward to helping build the school system in the new year.
Clay.

bell siphon, loop siphon = auto siphon

My siphons work without any u-bend on the bottom, when the flow is correct. Adding a t-piece or 90 deg bend can increase the range of operation:

G'day Clay

Nice system, very neat. and asthetically the Colurbond is nice too. Did the tank and Gb's cost much? and where from? If i may ask.

Erro

Hi Erro

i got them from rainfill tanks wholesale. the fish tank cost me about $250 and the grow beds were around $120 each

Calling Aquaponics Gurus....

i really need some advice. my system wont seem to get into balance. Plants are not growing well as you can see in the pictures. Lettuce have stopped growing, cucumbers are very yellow, tomato leaves are dying. nothing is looking dark green...except my pond!
The system is probably around 2 months old now and its cycled, pond went clear but now its seemingly going backwards...now the pond is looking like pea soup.

pH lately has been higher than 8.8 and i have been trying to remedy this with vinegar and molasses. this brought it down to around 8.2 for a while but now its back up again. Nitrates read zero, Ammonia reads zero (it might be 0.25 as the water is so green). Havent measured nitrite for a while. i have about 15 x 10cm goldfish and 5 x 5cm goldfish, i feed them about 1 tsp of fish feed in the morning and 1 tsp in the afternoon.

what i dont understand is, if there are no measurable nitrates and the plants look sick (obviously not getting enough nutrients), why is algae growing in the pond? what is making my pond so alkaline? it seems like i need more fish to drive the system so plants will have enough nutrients but with pond algae growing like crazy I would think that more fish would make the green pond situation worse.

I dont know which direction to head in...any help would be appreciated

cheers. Clay

pH 8.8... will bw seriously hindering your bacteria colony ... and probably wont be doing your fish any good ... or your plants...

Problem is with that pH and algael growth... correcting it with vinegar, will be totally short term as you've seen...

What's your source water pH......

IMO.... you need to shade your tank.... do a 50% water change... measure pH... and pump and aerate continuously...

Get some Diggers Hydrochloric acid... and adjust the pH back to 7.5 minimum...

How many and what fish do you have in there??

You might need to adjust the water over a week or so.... both with water changes and acid....

Changing pH rapidly would be detremental to your fish...

What's your water temp... ??

Hi Rupert

thanks for your advice. i will find out some of the info to your questions tomorrow. Temp when i got home at 5.30pm today was around 22˚C. in regards to stocking levels of fish, i have 15 x 10cm goldfish and 5 x 5cm goldfish

the source water was from my rainwater tank, which is empty now so i cant measure the pH of that but im now topping up with scheme water so i will measure and let you know tomorrow.

more to come.

thanks again

tested pH of my tap water, its 8.0 which i find surprising.

since i only have a small amount of pond water (<800L) im thinking of getting some sodium bisulphate. I dont think i want hydrochloric acid around the house and ive read a bit about sodium bisulphate on the forum and it sounds ok.

can someone advise me if they think i have enough fish to drive the system properly?

when was the last water change that you did?

No I don't think you have toooo many fish.

Cycling is a term used to discribe the water balance ( chemistry )
and occurs after the chemical balance is acheive.

Hi creative

the last water change i did, before today's water change was probably over a month ago or longer. I did a 50% change today. With my source water at pH 8.0 i dont think it will have done much, or will do much until i add some acid which im hoping to buy tomorrow.

i thought 'cycled' meant 'when the biology was in balance', i suspect its a bit of both. when i first started, my water was very green, then one day after about 6 weeks or so, the water cleared up. i thought that meant it had cycled.

since then it has progressively got greener and greener so im not sure whats happened. i did start with rainwater and then had to top up with tap water so that might be it???

thanks for the tip on the fish. i think i read a post from you talking about Hydrocloric Acid. Have you had success with using this?

Not only is Clays source water pH 8.0 .... but he has handfuls of shellgrit throughout his system..... full green algae... and current pH 8.8...

I understand that he did a 50% water change today.... and I've suggested that he halve his feed... (currently two teaspoons a day for 15 goldfish)....

And add a small amount of HCl.... and to test it with his "new" test kit that he's purchasing... and then post results here...

I suspect his bacterial colony is about shutdown at that pH ... what do others think...

I would use shade to slow/reduce the algae: either cover the whole fish tank (and deal with slowing growth of your water plants) or use boards or cloth or foam to make a floating shade for the main section of your open water.

Good luck, Clay.

thanks for all your advice.

though i dont have shellgrit throughout the system, there is no shellgrit in my system, i just have very alkaline tap water. I will add sodium bisulphate today and post results. ...im starting to wonder if that alkaline tap water is good for me and my family to be drinking all the time?

in relation to sun/shade on the fish tank, i never realised that would be such an issue. would floating plants like lillies or azolla etc do the same job if i could get good water surface coverage?

its just that ive got rectangular planter pots in my fish tank (see pic above) growing kangkong, waterchestnuts and watercress so it would be hard to cover the pond without removing them. if i have to i will.

Yep, I noticed that. But if you had something that just covered most of the open area between the plants that would make a big diff.

did another water change. here are my pH readings

day1: put in half tblsp (12g) of sodium bisulphate in morning, tested late afternoon, no change still 8.8 or over. put in one tblsp that night
day 2: tested in morning looked to have gone to 7.8 but then the sample changed and went dark purple. tested in afternoon and pH was 8.8 or over. added 2 tblsps (48g)

see what happens when i test in the morning.