Using Parent-Child Configuration with Vortech Pumps and Max Speed

[Wingzinco]

Hey all. I've seen another thread that's a few years old in regard to what the max-speed setting does when you set up Vortechs in a parent-child relationship, but it might be worth bringing up some findings. I haven't done extensive testing on this yet, but maybe we can figure this out with different modes.

I have a MP40 on each side of my four foot tank, running in anti-sync, with the left side acting as the parent and the right as child. Because I also have my return running in the same direction (right to left), I wanted to reduce the max flow on the right MP40 so that the left could counter the flow and create better flow on the right side of the tank. I've tried reducing the right (child) max speed in Mobius, but was frustrated because it didn't seem to make any difference when watching the flow speeds.

The logical thinking is that the child max-speed should be a percentage of the parent, but clearly not the case. When playing around with it, in both Expanding Pulse mode and Lagoon Mode, this is what I found:

Expanding Pulse

• Parent pump max-speed set to 25% - GPH range of 1550 - 2280
• (1) Child pump max-speed set to 1% - GPH range of 1550-1580
• (2) Child pump max-speed set to 5% - GPH range of 1550-1700
• (3) Child pump max-speed set to 10% - GPH range of 1550-1850
• (4) Child pump max-speed set to 15% - GPH range of 1550-1990
• (5) Child pump max-speed set to 20% - GPH range of 1550-2140
• (6) Child pump max-speed set to 25% - GPH range of 1550-2270

Lagoon

• Parent pump max-speed set to 13% - GPH range of 1500 - 1940
• (1) Child pump max-speed set to 1% - GPH range of 1580-1595
• (2) Child pump max-speed set to 5% - GPH range of 1580-1700
• (3) Child pump max-speed set to 10% - GPH range of 1580-1860
• (4) Child pump max-speed set to 15% - GPH range of 1580-1935
• (5) Child pump max-speed set to 20% - GPH range of 1580-1950

So, it seems to me that the max-speed slider does not act as a flow percentage of the parent (at least in anti-sync), but more as a limited flow range of the parent. In both cases, 25% in Expanding Pulse and 20% in Lagoon, you hit a max of that variation in flow and it eventually acts as if it's 100% of the parent's flow. Going above these numbers does not affect the child in comparison to the parent. While keeping the max on the child to 1%, almost keeps it at a steady flow rate, which defeats the purpose of certain modes in many cases.

I plan to test this more, but in the case this was useful and anyone else wanted to give it a try, it would be interesting to see other findings. It is certainly unintuitive and isn't representative of actual effects.

 

[Sisterlimonpot]

I have to confirm if this is still true (a lot of things have changed with parent/child, sync/anti-sync lately), but the percentage setting for the child was in relationship to the parent. If the parent was set to 50% and the child at 100%, the child would run the same as the parent (50%). To drive home this scenario if the child was set to 50%, it would be half the parent (25%).

I think what you're experiencing might be a bug in the software. What youre seeing in mobius isn't really providing feedback of what the pump is actually doing, rather you're seeing a display of GPH based on math in the software. And that can easily be explained by wrong equations in the software.

What would be helpful is to try this experiment with the pumps in constant speed and use your hand to feel the current from various percentages of the child to see how it compares to the parent.

I'll reach out and see if the previous way child percentages work are the same way. There's one big reason why it wouldn't, but that'll have to be another discussion in the future.

 

[Wingzinco]

I have to confirm if this is still true (a lot of things have changed with parent/child, sync/anti-sync lately), but the percentage setting for the child was in relationship to the parent. If the parent was set to 50% and the child at 100%, the child would run the same as the parent (50%). To drive home this scenario if the child was set to 50%, it would be half the parent (25%).

I think what you're experiencing might be a bug in the software. What youre seeing in mobius isn't really providing feedback of what the pump is actually doing, rather you're seeing a display of GPH based on math in the software. And that can easily be explained by wrong equations in the software.

What would be helpful is to try this experiment with the pumps in constant speed and use your hand to feel the current from various percentages of the child to see how it compares to the parent.

I'll reach out and see if the previous way child percentages work are the same way. There's one big reason why it wouldn't, but that'll have to be another discussion in the future.

Hey, thanks for the response. Yes, I agree with you that should be the way it works and good idea with the constant flow test, I'll try to get to this tonight. That being said, if that were the actual case, you would assume that by setting the child to 1% would barely create any flow at all. So, the theory of a bug would make sense if I saw the higher flow numbers in Mobius but actual flow was not happening. That is not what's happening at all, I barely notice any difference in the tank flow at all when it comes to the movement of corals (torches, etc) and seeing particles in the water column getting blasted toward the other side. Clearly, this isn't the most accurate measure, but it's quite clear that flow isn't 1%, 5%, 10%.

Any info you can find would be fantastic. It's difficult to find any real documentation on this. Thanks!