Backyard Aquaponics
A place to discuss aquaponics

Just having another look at the pics of the radishs... thought.. just about time for some Dipel there Neil...

Then I spotted the little villan.....

I get a few of those little green devils. I don't mind so much, just go round picking them off. A few holes in leaves doesn't bother me.

I haven't seen them attack my lettuce yet. Don't they like lettuce?

No they dont like lettuce - but I would still stay on top of them. Try to keep the population low, or they decimate things like cabbage, cauli, and broccoli.

Dipel is safe and good

Geez, OB, thought we were still talking about cockies for a minute!

Fishfodder.... um fishfodder....

Hi All and Merry XMAS

I was thinking of growing some yabbies in a 250 litre fibreglass tub (one of Murray's small grow bed/fingerling tanks) how many do you think I could grow in that volume of water.

I currently have about 80 small to medium sized SPs in my main tank and the the system is coping. Ammonia and Nitrite are both 0, nitrate generally sits on about 20.

Am I right in saying that yabbies add less ammonia to the system and I could run a tub of yabbies without adding more growbeds.

Any thoughts

Cheers

Yep, no worries Neil ... you can always grow duckweed on the tank surface...

Sucks up the ammonia... helps keep the little buggers in the tank... shades them... and Silver Perch don't mind eating a bit of duckweed either ....

250L tank...... probably about 20 - 25 max.... with lots of hides...

I agree Rupe but waas about to add this

I'd say not...
Your Nrate level are not being reduced enough by the plants.[takeup]
Is your growth leggy? (heaps of growth - not many flowers
Sorry I have not flicked thru your thread in a while

Hi C1

Growth is good, I am growing mainly leafy veges, spinach, lettuce etc so the flowering issues is hard to ascertain. I thought a Nitrate level of 20 was reasonably low?

Thanks John

I will PM you for some details.

~0+ is better, but I think that is the maturity of the system.

Yep, maturity is definitely lacking. I have some tomatoes and eggplant in, but they are basically dormant. Spinach and lettuce are going great guns.

The tomatoes I got from an elderly Hungarian man. They are old hungarian heirloom varieties so I hope I get a few tomatoes just for the seed.

I have a slightly different take on it. I'd rather keep it at 20 than 0. At least at 20 you know you can keep an eye on it (ie. plant more plants or reduce feeding slightly if it starts to creep up) and you know your plants have the nutes they need.

If you're reading 0 nitrate you have no way of knowing how many nutes your plants are going without. 20 nitrate won't harm your fish, but 0 nitrates and over population of plants will stunt/slow the plant growth.

True enough MrOrange... but the corollory is that a zero reading means the plants are using the nutrients available... and will indicate any deficiencies pretty quickly...

Also implies an established, balanced, mature system.... so you can always increase your feed a little or add a few more fish...

As you though a reading of 20 isn't going to hurt your fish.... in fact I've been told that readings to 400 are safe.... and members have been running around a 100.... but panicked at the unknown... and employed RSG filters to lower the nitrates...

Would you necessarily notice though? What if the defeciency was not visual and was reduce rate of growth instead? Pretty hard to tell if your plants are growing 10 or 20% slower than they should due to lack of nutes unless you had a 2nd system to compare to.



I agree, though if you're showing 0 nitrates I would recommend upping the feed rate as something is inevitably missing out.



Yep - I've kept & bred fish for many years. With aquariums I would keep water under 100 nitrate by means of part water changes as required. Reason being, higher nitrate levels and sunlight leads to aglae growth and the less cleaning I had to do the better. Super high nitrates also discolour the water (wouldn't notice it in AP, but a tank inside the house it has a 'tinge') and I've found stunt fish growth (in my fry tanks, always kept nitrates very low in fry tanks, ie less than 40.).

0+ mean zero and above. Might just be keeping it closer to the zero.