Backyard Aquaponics
A place to discuss aquaponics

6 hrs is pretty good. I wonder what the L/min drops down to if it is 11L/min on AC if it would be enough for 40 SP?

Mind you, on the batteries, the air out put from the Otto drops down to about 3000cc/min aeration on battery... not a lot... 3litres/min...

Think it was 6 hours... at least 4hr... might vary according to quality of the batteries you use...

Hmm... Doesnt sound like much air ,does it. I have to get system up and running because it will happen if im not prepared. I have 4D batteries to put into Otto but not rechargeable so I imagine if I left them in the machine they would discharge in next to no time. I will have to run out to system and put them in if the power goes out.
I have a LED night light which turns on at dusk and off at dawn and can see it through laundry door so I know if power is still on.
My security system inside house beeps every minute until I acknowledge it if power goes out so another warning for me but if im at work it will be major tragedy for fish.
I would be much happier with a bigger set up.

Most people run good quality rechargeables in the Otto... some say the Otto will actually "trickle" charge them... supposedly...

I use the ProAqua X-28 for any tank over 1000L.... twin oulet with a builtin rechargeable 6v battery.... no observable difference in air output on battery....

No. This has been confirmed by Joel.

OTTO AIR PUMPS DO NOT CHARGE THEIR BATTERIES.

Here's the link to the ProAqua... http://www.guppysaquariumproducts.com.a ... d_383.html

Has a high and a low "intermittent switch"... that pumps 10min on/off....

In intermittent mode the battery will last at least 16 hours... (as long as the battery is in good condition).... you need to cycle the battery by unplugging the mains every 1-2 months... and running on battery for about an hour or two...

I guess while I am planning a bigger backup I should cover the fish with rechargeables in the Otto. I just baulked at paying $50 for 4 Varta rechargeables when I could spend that on something better. But $50 to cover my fish lives is really not an issue, is it?
Stupid me!!!

That looks like a good one Rupe.
And cheaper than rechargeable batteries.
What is the air flow like?

i bought one of these... outside of the battery being doa and the company saying they sent a replacement but i never got it.. it works pretty well... the replacememt battery only cost $13 from an auto electrician...

i use it as the main air supply for my system and have the air stones near the base of the ibc.. even on the battery backup it supplies air to the tank without a hassle..

Having a battery backup and inverter may be a a good investment. Depends on the chances of a power outage effecting your fish.

Running your system on a battery bank all night and charging again from a PV system is not as effective as selling power in the day, buying power at night, and keeping your batteries charged up in case of an outage: losses from charging are quite significant and your loss of battery life from charge/discharge cycles is expensive as well.

I'm not saying that solar/battery is not effective in any cases, just that grid-tie PV is hard to beat.

I'm tending toward the idea that the best backup system is a really large fishtank with few fish in it. Power goes off for a day and the fish are still fine.

Mine does a child working at Jaycar (where I bought the rechargable batteries from) tested the unit for me and it definately has a very slow trickle charge output to the batteries in 240V mode, I even use it to charge batteries from my torch.

The problem I have with it is the water pressure at the bottom of my FT and the low out put of the pump when powered by batteries means I need to suspend my airstone half way up the water colum to get bubbles (works fine on the bottom with 240V).

To get a better battery back up using stuff I already had around I took a leaf out of OBO's book and run the otto off an inverter from a deep cycle battery constantly charged by a 4 amp battery charger.

I'm completely off the grid (for about 17 years). $400 US seems very doable for a small system. Small inverters are very inexpensive. Deep cycle batteries aren't too bad...

I've only got a small 20 gallon system inside which uses something like 10 watts/hour (or less). I've been debating setting up a separate system for a larger outdoor AP setup. I couldn't run it in the winter anyway (way too cold here) so I wouldn't have to oversize it.

What is your power system consist of, and what sort of power usage/generation is normal for you?

After about 17 years you would have a very sound idea of what the running costs are?? Photos would be great too.

I actually haven't thought about running costs for a long time. I had to buy a new generator this winter which was $1000 - it runs on gas which is a pain. We used to have a propane one that could auto start at a set voltage drop. My husband has been trying to fix it but propane is now 2x the price of gas so if we (he) can deal with bringing gas up once a week maybe its worth it. We've decided it is worth it to run the generator for the 15 minutes it takes to draw a bath in the evening (rather than draw down the batteries). Other than that, we'd need consecutive rainy days to get really low on power.

As I dwell on running costs I'll just note that our fridge is a 12v SunFrost, our hot water is a propane AquaStar on demand unit. Stove and dryer are propane. We have a very tight house (R36 on 6 sides) which only take 2 cords of wood to heat. On sunny days it heats pretty well just with the sun. Stays cool in the summer.

Right now it's slightly overcast and we're getting 27 amps in. Our highest ever was 82. The only thing running is the outlet with the phone, timer for water pump, air pump, lap top, and modem with wifi of course. This shows up a 0 draw on our Outback inverter. We used to have a Trace that showed our usage more accurately. I'd guess 10-15 watts. The kids are in school

Yes i to would like to see photos of your whole set up [house the lot ]
Please