Backyard Aquaponics
A place to discuss aquaponics

hi everyone got more questions. i still have green water with no noticeable change .all test are normal, i've been reading as much as i can on ap systems,but there is so much information it's getting confusing at times. would it help if i added duckweed to the tank until my plants start growing, because i've lost some due to a cold front we had. was also thinking about removing the nft tubes. and putting up 4 more grow beds made from half cut plastic barrels to increase grow bed surface aera.could anyone tell me what the ratio needed for my system.and do i need to cut back on air flow at night or stop it all together do to the continous flow. also is flood and drain better than continous flow or is this just a personal preference. when in doubt ask.

Howdy, CC. Welcome aboard.

A couple thoughts here....the algae can cause ph daily swings. It produces CO2 at night (becomes carbonic acid and drops the ph) and sucks all available CO2 during the day (lowering ph). What time did you get that water sample that tested 8.4? Getting a test kit and hitting it morning and eve might tell you something.

A couple other thoughts to cover the bases: What is the ph of your water source? What type of gravel are you using? I would be surprised if the oyster shell is raising the ph that high as TCLynx has tested shell in her growbeds. Still, you could take a cup of tap water and shell and test ph in a couple days. Same with gravel.

Your ammonia, nitrite, and nitrate look good to me. Adding duckweed will shade the algae nicely and stop reproduction, but will also take ammonia out. Nice while the system is cycling or if nitrates are too high in a cycled system, but robs your plants if things are going well. I like the suggestions people have been making that you shade your FT mechanically. Shade cloth, scrap lumber, whatever.

Disclaimer: this advice comes from someone not fully qualified to give it!


tagline: Kids in the backseat cause accidents.....accidents in the backseat cause kids.

Flood and drain seems to be the way to go CC. You have no Nitrite, so I would say you have enough grow bed space for now

Disclaimer: this advice comes from someone not fully qualified to give it!
that should probably be added to everyone who has a post count under 1000

if i am correct about the flood and drain systems that i have been looking at. the water flows from out the pipe across the beds at a certain hight then over flows into a drain pipe back to a tank or into the main fish tank.my ebb and flow tray i use for hydroponics .a pump fills the tray to a certian hight runs for 20 to 30 min. then the remaning water back fushes through the pump to drain the tray completely.what system would work better.and how large are the holes in the pipe need to be,because i will replace my 300 gph pump to a 1900 gph unit with a low water shut off.

Hi Cajun
I'm a newbie and I've just gone through the green water stage. I got advice from the Forum, and this is what I did:
Covered 70% of the tank
Installed an air pump
Stopped feeding for 3 days Amazing results: the green stuff broke up and the fish (Silver perch) must have eaten it. The water is now clear, I can see the bottom, its about 750mm deep(2 feet 6 inches) and I can see the fish. ph is around 7. Its flood and drain and its now cycling. plants are growing. I think the secret is light and oxygen, less of one and more of the other.
good luck
Rodney

I find that if the green stuff starts taking over making me fear the coming of the SwampThing - stopping feeding seems to help. Once it clears out, it is time to start feeding again. Tilapia really seem to like the green goop.

Time to put netting on the tanks too - even though they are in the shade.

thanks i will try shading the pond with a darker cover .i have an air pump it's a sunleaves 690gph with a 3 inch air stone this was in the tank from the beginning ,was wondering if i should cut back air flow. and i am feeding the fish common ditch minnows, because i could not get them to eat the dry fish food at all. about how long can catfish live without eating.

Dont cut back air - you want excessive air or the fish will struggle.

Yea, air is good. Unless of course you are bubbling the water so strongly that the fish are being carried to the surface in giant air bubbles.

Air is especially needed overnight and even more so if you are dealing with algae or pea soup!

CrazyC, no one picked up on your back flush comment.

No, water is fed from the top so no back flushing will occure through the pump.

what few cms of water is left at the bottom is of no concern

The main draining is done via the stand pipe which has an inner drilled pipe.

inflow = more than drain so bed floods to top of inner pipe and overflows down drain.

When pump stops, the fill slowly drains out the drilled inner pipe.

thanks steve ,that clears up a few questions i had about the systems i've seen. what about changing my pump from a clear water magnetic drive to a dirty water sump pump that has about 3 times the flow.and will change system to flood and drain.

water is showing signs of clearing. is there a need for the bio filter i instaled with the oyster shells.or should i get rid of it, because one thread mentioned that it could cause problems with controling ph. and has anyone used a ph doser in an ap system?

pH doser in BYAP! Nah, would be better if you have enough biodiversity for balance to ocur naturally! Unless you have very bad water, in which case the fish wont survive anyway.
IMHO, but wait for more diverse comments.

crazycajun, hello there neighbor (sorta). I have heard of the barley solution for algae. Never tried it. I think it would be okay for your fish, not sure about the other plants if it kills algae. Have you ever considered a Ultraviolet filter to kill the algae? They work but they are a bit pricey.

I agree with hydrophilia about the CO2 at night causing carbonic acid and lower pH in the morning. But I have seen, in a pond situation, pH rise in the afternoon. I know little about aquaponics but something is causing a nutrient source for algae growth. How does the intended plant growth look? I would think it would be good if the algae is growing well.

Catfish can go for months without food if the water is cold. Yet I think that they are eating something that is converted into usable nutrients for the algae. The catfish must be eating the minnows. Are you adding minnows often? The minnows must be the nutrient source. Shading the fish pond would be the easiest algae elimination remedy. I would shade the biofilter as well to prevent algae growth in it..

About getting rid of the biofilter. Hmmm. I thought the beauty of aquaponics is that the plants were the biofilter. But the oyster shells should buffer your pH from broad swings. So I can't answer that either.

hi neighbor
the plants are doing fine they are starting to grow better with the warmer weather. i have considered using a uv filter, but what i found out about them is that they would kill the binifical bacteria as well as the algae.my algae is clearing. i'm thinking of putting in more grow beds and only using them as bio filters for now.i've cut back on how much i feed the fish. as the weather gets warmer i will neeed to feed more.
I would like to know has anyone done a u-pick garden from an ap system and was it successful.