Bidirectional tidal flow

[The Codfather]

Don't know about prices, but here is a little info. from sequence:

http://www.mdminc.com/Doc/Sequence%2...ata_Sheets.pdf

[golf nut]

You can buy an $8 reed switch, sense the position of the drum then hook that to an Areotronics timer, select the time delay and you are done like dinner. net cost $39 .

[MitchM]

Codfather, thanks!

golf nut,

So I would use a 2-way OM unit?
What is a reed switch and Areotronics timer?

Thanks,
Mitch

[sphelps]

A reed switch works on magnetism, same type of switch you'd find on windows and doors for alarms. Problem is the OM has a thick plastic casing and you'd need pretty powerful switch to work properly and you would have to enclose one end within the drum which offers will space. Plus you'd need two switches for the two positions meaning you'll also need a smart relay to understand the two switches and control the system accordingly. It's certainly not as simple as described and the cost would be beyond $39.

[sphelps]

Not to mention the OM drum is driven by powerful magnets, I can't see a reed switch working properly to begin with.

[lastlight]

If you just tee off your closed loop pump and have a valve on either side of the tee why do you need 4? Are you concerned about valving off inlets on either side too? If the inlets were more or less centered why not use just 2 valves?

I think a guy on RC bought a morized butterfly valve or something like that by Hayward. They're pricey but from what I read the pricey ones are extremely reliable.

Overall likely cheaper to use a pair of DC controlled pump for each side. Red Dragon is apparently releasing new pumps as the previous generation had issues. I've heard good things about similar pump but can't quite recall the maker or the name sorry.

[golf nut]

Originally Posted by lastlight

If you just tee off your closed loop pump and have a valve on either side of the tee why do you need 4? Are you concerned about valving off inlets on either side too? If the inlets were more or less centered why not use just 2 valves?

I think a guy on RC bought a morized butterfly valve or something like that by Hayward. They're pricey but from what I read the pricey ones are extremely reliable.

If you are only switching every 5 hours they will work fine, the rapid sequencing is their downfall.

[sphelps]

Originally Posted by lastlight

If you just tee off your closed loop pump and have a valve on either side of the tee why do you need 4? Are you concerned about valving off inlets on either side too? If the inlets were more or less centered why not use just 2 valves?

I think a guy on RC bought a morized butterfly valve or something like that by Hayward. They're pricey but from what I read the pricey ones are extremely reliable.

If you had a common suction 2 valves would work. I think ideally to create the cross flow you need a suction on one side and the output on the other so in this case you would need 4, which is what I was talking about.

[golf nut]

Originally Posted by sphelps

If you had a common suction 2 valves would work. I think ideally to create the cross flow you need a suction on one side and the output on the other so in this case you would need 4, which is what I was talking about.

Here is a quick bad video, there are 8 holes drilled , 4 at either end of the tank for coverage, the lower holes are C/L feeds, the uppers are C/L returns, they are being switched by a common drum, when water enters top right it is being removed bottom left and vise verse, if you watch carefully you can see the pellets being drawn in from the bottom. the pellets are an injection molding pellet about the same specific gravity as water.

just one pump.


http://www.youtube.com/watch?v=XxlOvNN-OPE

[lastlight]

Here we go:

Abyzz pumps by Venotec.

http://www.korallenzucht-wendel.de/g...n/venotec.html

http://www.youtube.com/watch?v=wFGASFHEWL8