Backyard Aquaponics
A place to discuss aquaponics

Thanks Janet and Les

hey guys, so the only real diff. between the Nitrate rsg and the iron rsg, is the iron?

so the iron chelating rsg will also nitrate off gas? Am thinking about putting one in the old mans system but he is already struggling with not having enough nitrates

Janet or Les, how long are your pump off cycles. There are a few people who dont run their pumps at night, would this be a problem with your filter drying out and air coming in?

Les runs continuously (with autosiphon or actuator) KE14.

could always run a tiiiiny pump 5 - 10w just for the rsg

Added an RSG filter to my grow-bed today. Have my inlet pipe running over the top of it, with a small hole drilled in the inlet pipe to provide water to the RSG. Nitrate is currently 80+, so will monitor over the next few weeks to see how it goes.

well, i'll have to get one then, they seem to be all the rage!

"tut, i went to steves, tut, he didn't even have a rsg, tut tut, scoff"

In an ideal world I would never run an RSG, preferring to grow plants to use the nitrates, but when I am still in construction mode, it may be a good option.

Having said that - I am of the strong view - always have been, that my GB serves this same purpose to a certain extent when functionning in its normal way.

My nitrate leve of about 80 has not rissen over the last 6 weeks eventhough I went from hardly feeding the fish ever to feeding 100-150grams a day again when the weather got a bit warmer. I reckon my nitrate is gassing off currently.

we need more fish, not more RSG

Well get some then!!!!!!!!!!!!!!!!!!!!!!!!

soon

KE, I would say yes - the way to get around this would be to flood the bed and leave it flooded overnight so air doesn't get into the filter...as vb said, I run continuous flow


I tend to agree with you vb, my main reason for trialling one was to use a quarantine/purging system and not have to worry about nitrates building up to high levels

Once I'm sure it works I'll probably remove it. I'm kinda more interested in finding out where the equilibrium is in my system without an RSG. From experiences to date, in my system gassing off seems to keep it somewhere between 80 and 160.

KE, I run my pump all the time. The whole point of an RSG filter is -not- to let it dry out. You don't want air in there.

Steve, I suspect an Iron RSG may also offgas nitrates. You could just try burying some iron in the bottom of the growbed if the water doesn't drain completely. That way you are not increasing anoxic volume, but just adding iron to the volume you have.

VB, I agree, I suspect that there is some offgassing that happens in the bottom of any growbed. Adding an RSG filter just gives you more capacity. I would much prefer not to need an RSG. However, it got me out of a bad mess. I'm just about ready to remove my remaining RSG--plant volume seems to be handling things better now. I've been adding shade-loving tropicals.

agree with the not letting air in. Anerobic bacteria can be just as sensitive to O2 as aerobic bacteria are to O2 depletion!

problem with the old mans biofilter is that its ALL really well oxygenated and is a completely unflooded open trickle system. will create an environment for him as iron def. is getting bad and as i suspected putting iron into the aerobic filter has done nothing.