Backyard Aquaponics
A place to discuss aquaponics

I'm happy with the digital timer I bought (you can do a search for it)- but it said indoor only and they meant it! I can't use the 2 I put in my hoop house, they LCDs aren't readable anymore.

Fair call - do the clean water pumps have a strainer to ensure larger particles can't enter?


Ingenious! That's what I'll do.

Well, the overlapping mechanical timers doesn't work. Something I overlooked is the second timer (the one plugged into the first timer) only receives power for 15 minutes every hour, thus doesn't rotate at the same rate as the first.

Looks like the only option is a Sentinel DRT-1 (or similar) digital timer, that can do a 2 minute power on each hour. Anyone know of a stockist?

You don't need to pump for only 5 mins.... 15 mins, with an overflow standpipe... would be just fine... and one mechanical timer will do the job...

I have always used mechanical timers the first lasted 2 1/2 years this second one is going strong
it runs my 28000 lt hr pump on for 15 min so the growbeds fill in 3 min and the other 12 min the overflows take up all the slack
the only reason i use a mechanical timer i cant work out how to program the other bloody things

The reasons I want to pump for only 2-3 minutes are my pumps are overkill for the job (400W) and fill the GB in about 2-3 minutes, but only cost $70 each from B.

Also, for some reason, the overflow standpipe doesn't seem big enough to stop the GB from overfilling. I'm using 40mm PVC and it still can't escape quick enough. Maybe it's due to this system having only a few holes down low on the 100mm shroud pipe. The overflow standpipe height is about 5cm below the gravel level. I might add some more drain holes on the standpipe to see if that eliminates overflowing. I'm unsure of more holes in the shroud pipe would have made a difference, but I doubt it.

All this would be negated by having a timer that could do 3min on/57min off cycle though.

Maybe I shouldn't have been such a tight-arse on the pumps, but at $70 with a float switch and easily accessible if I need a replacement, they seemed like a good idea at the time.

I take back what I said about being happy with the digital timer. It reset while the pump was running. Several gallons wound up on the floor (inside!) but most of the water went back into the FT from the GB.

A digital timer will work but you'd better have an overflow that will prevent disaster if the pump fails to turn off. Especially with a 3 minute fill time. There are many digital outdoor timers available.

That do a 3 min on, 57 min off every hour? I can only seem to find the Sentinel.

You are right about the overflow though. As soon as this rain nicks off, I'll be sorting that out as a high priority.

Hey Ranga I have the same pump I think and for the same reason...it all ads up. I got a digital 'indoor only' timer from B's for $15 and it runs fine down to 1 minute. Limitation is it only has 20 on and off asettings, but with 15mins on and 55 off it easily stretches 24hrs. It is outside but is covered by something i adapted to make sure i doesnt get wet. I also siliconed around it and in the screw holes which had a bit of rust.... i used to play around but now I let the system overflow for 5-10 mins depending on the bed. I figure its good for the system etc.... My overflows are 25mm x 6 and they dont flood...
more holes will make the bed fill slower but once its full if the overflow cant handle the extra i cant see it making a difference...

Many available at 120 V anyway (check amazon).

Have you thought about bleeding off some water so it doesn't go to the GBs. If it went back into the FT it would add lots of aeration.

[quote="bonsaibelly]
Hey Ranga I have the same pump I think and for the same reason...it all ads up. I got a digital 'indoor only' timer from B's for $15 and it runs fine down to 1 minute. Limitation is it only has 20 on and off asettings, but with 15mins on and 55 off it easily stretches 24hrs. It is outside but is covered by something i adapted to make sure i doesnt get wet. I also siliconed around it and in the screw holes which had a bit of rust.... i used to play around but now I let the system overflow for 5-10 mins depending on the bed. I figure its good for the system etc.... My overflows are 25mm x 6 and they dont flood...
more holes will make the bed fill slower but once its full if the overflow cant handle the extra i cant see it making a difference...[/quote]
Can you remember what model timer? Does it have 20 on and 20 off settings (40 combined) or 20 in total?

I think my GB is flooding because not enough water can get through the shroud pipe due to too few holes. Trouble is, making more holes means pulling the shroud back out - major PITA! Maybe a right-angle drill adapter might fit down there?

Thanks!

Ok, i get it , sounds lika a PITA. I'll take a pic tonight/check tonight...its 20 cycles on, 20 off. Other way would be adding more GB's to take some flow or redirecting into the tank as suggested by CjinVT

Thanks - 20 on, 20 off sounds great. Thanks for checking for me.

I reckon a few more drain holes will fix the problem - hopefully I'll sort something out without too much fuss.

Hey ryangus, didn't you read this in my original post.................

Cheap way of getting timing down lower than 15 mins is to piggyback 2 together. NO not 2 mechanical ones.... 1 mechanical and 1 electronic

How do you think I found out Made the same mistake.

How does the electronic get it's power?

Regardless, if I can get one that does 20 on and 20 off cycles cheap enough, that will do me.