Merits and Drawbacks to pulsing returns?

BRS

JNalley

Valuable Member
Review score
+0 /0 /-0
View Badges
Joined
Oct 12, 2021
Messages
1,190
Reaction score
1,548
Review score
+0 /0 /-0
Location
Grandview
So, looking at a lot of the latest DC Return Pumps and a lot of them (including submersible only pumps) are including some kind of pulsing mode. I will preface this with the fact that I am going to be starting my first build with a sump ever, I have had a few FOWLR tanks in the past, the longest one running for 10-11 years, but those tanks were all run on canister filters, powerheads, and hob skimmers. I just recently got an AIO for my daughters first tank and can already see the benefits that a full sump system will provide for me.

All that said, as I understand it most of the time return pumps are run at a single consistent speed to keep the return chamber level from fluctuating and triggering ATO's. So why would manufacturers suddenly start making return pumps (a submersible only should be used exclusively as a return I would think) that have pulsing type modes? I ask because I was considering purchasing two Sicce SDC 3.0's and running a dual return on my new tank. This helps for redundancy, but because the returns are posted at each end of the back panel, and these pumps have a "tide" mode, I was wondering if letting them mimic a tidal current (opposite each other in a counter-sync/anti-sync mode), while my wave makers provided the randomized flow patterns would have any benefits or drawbacks. presumably, if they are 180 degrees out of phase with one another (as a true anti-sync should be), the flow would be consistent, and therefore the level in the return chamber should be constant, no?
 
AS

KrisReef

5000 Club Member
Review score
+0 /0 /-0
View Badges
Joined
May 15, 2018
Messages
6,349
Reaction score
18,532
Review score
+0 /0 /-0
Location
ADX Florence
Great question. I think you and I appreciate the idea of tidal exchange and the potential increase in "random flow" from a pulsing pump back into a tank. I have not used one (or two) of these for return and wonder how there operation would impact auto top off working in the sump? I would be cautious setting one up to insure the salinity in the system wasn't going to be surging with the tides?
 
OP
JNalley

JNalley

Valuable Member
Review score
+0 /0 /-0
View Badges
Joined
Oct 12, 2021
Messages
1,190
Reaction score
1,548
Review score
+0 /0 /-0
Location
Grandview
Way too hard (impossible) to balance the drain, it will make noise.

Return pumps should be constant - If they have a pulsing or wave mode it is meant for when they are used in closed loops.
I'm not arguing, just trying to understand.

Look at the Maxspect Jump DC Returns, they are submersible only pumps and impossible to use in a closed-loop (from what I understand), they have 4 different pulse modes regardless of this fact.

Also, a quick pulse is not really what I was thinking here. In a tidal mode setup on my 2 Sicce Xstream SDCs, one runs at 5% while the other runs at 100%, they then move to 10% and 95% respectively, and continue until the opposite is true. It's done completely 180 degrees out of phase with one another, so there is always the same amount of water being moved, it just slowly changes hands from one side to the other. The tidal mode would do this over the course of 6 hours, wash, rinse, repeat. So would it really be "impossible" to balance the drain in that setup?
 
OP
JNalley

JNalley

Valuable Member
Review score
+0 /0 /-0
View Badges
Joined
Oct 12, 2021
Messages
1,190
Reaction score
1,548
Review score
+0 /0 /-0
Location
Grandview
Great question. I think you and I appreciate the idea of tidal exchange and the potential increase in "random flow" from a pulsing pump back into a tank. I have not used one (or two) of these for return and wonder how there operation would impact auto top off working in the sump? I would be cautious setting one up to insure the salinity in the system wasn't going to be surging with the tides?
Yeah, it's just a thought right now, and since I am going dual return anyways, I might attempt to run it fallow for a week or so in the tidal mode just to see how it performs and how it affects other things. But at the moment it's just a thought, and I really do appreciate the idea of tidal exchange.
 

Vivid Creative Aquatics

Upgrade Your Flow!
Review score
+0 /0 /-0
View Badges
Joined
Oct 12, 2017
Messages
1,032
Reaction score
1,328
Review score
+0 /0 /-0
Location
Phoenix, AZ
I think running the return pumps like you have described would be problematic.

The main issue as you have already identified would be maintaining the balance of flow vs drain back and the water level in the sump. With inconsistent sump water levels, there then may be no reliable way to measure evaporation in the tank which would make topping off the tank difficult.

Another solution to create that randomized flow through the return lines would be to use our Random Flow Generator® Nozzles. They can create that varied flow patter from a steady flow source, like a return line

This would allow you to have both steady constant flow from the pump AND randomized, more natural flow within the display tank.

What size is the tank, and what size will the return lines be? Also what do you think your head hight will be? I can help calculate GPH and then suggest a properly size RFG if you would like
 
OP
JNalley

JNalley

Valuable Member
Review score
+0 /0 /-0
View Badges
Joined
Oct 12, 2021
Messages
1,190
Reaction score
1,548
Review score
+0 /0 /-0
Location
Grandview
I think running the return pumps like you have described would be problematic.

The main issue as you have already identified would be maintaining the balance of flow vs drain back and the water level in the sump. With inconsistent sump water levels, there then may be no reliable way to measure evaporation in the tank which would make topping off the tank difficult.

Another solution to create that randomized flow through the return lines would be to use our Random Flow Generator® Nozzles. They can create that varied flow patter from a steady flow source, like a return line

This would allow you to have both steady constant flow from the pump AND randomized, more natural flow within the display tank.

What size is the tank, and what size will the return lines be? Also what do you think your head hight will be? I can help calculate GPH and then suggest a properly size RFG if you would like
I went a different route for now, since I will be moving in 2 years, getting the tank I want versus the tank that makes sense came into play and so I went with a Reef Octopus Octo LUX T90, which has a weird return.

That said, I'm still compiling information on the tank after we move. I'm thinking a 80-90 Gallon, ~36 x 24 x 24, Fiji Makes an 80 in this form factor I think it's 36x24x22 or something like that, with Dual returns.

I'm still curious if a Tidal pattern can be made from it though, I might do some experiments in a smaller form factor to see what happens because a 6-hour hand-off shouldn't really cause that kind of disturbance if they're truly out of sync with one another...

Unfortunately, your RFG Nozzles won't fit on the new tank, otherwise I'd take a look... the return is a grate built into the back
1643483129492.png

But I actually need to come up with a solution for it, because it shoots directly at the surface and the front glass, which creates a vortex in the corner that makes bubbles about every 15-20 seconds...
 

Vivid Creative Aquatics

Upgrade Your Flow!
Review score
+0 /0 /-0
View Badges
Joined
Oct 12, 2017
Messages
1,032
Reaction score
1,328
Review score
+0 /0 /-0
Location
Phoenix, AZ
I went a different route for now, since I will be moving in 2 years, getting the tank I want versus the tank that makes sense came into play and so I went with a Reef Octopus Octo LUX T90, which has a weird return.

That said, I'm still compiling information on the tank after we move. I'm thinking a 80-90 Gallon, ~36 x 24 x 24, Fiji Makes an 80 in this form factor I think it's 36x24x22 or something like that, with Dual returns.

I'm still curious if a Tidal pattern can be made from it though, I might do some experiments in a smaller form factor to see what happens because a 6-hour hand-off shouldn't really cause that kind of disturbance if they're truly out of sync with one another...

Unfortunately, your RFG Nozzles won't fit on the new tank, otherwise I'd take a look... the return is a grate built into the back
1643483129492.png

But I actually need to come up with a solution for it, because it shoots directly at the surface and the front glass, which creates a vortex in the corner that makes bubbles about every 15-20 seconds...
that is an odd looking return - is the flow entering through that grate in the middle of the photo?

Fiji makes a decent aquarium, and i believe you are correct, that the larger sizes do have dual return lines - one in each corner. In that setup, the RG is a great choice and can really create soem movement in tank.

as far as making tidal flows - this is possible - in fact we do this in our own aquarium her in the office using a dual closed loop setup. our 134-Gallon Cube has two closed loops, each with their own pump. The two loops ramp up and down opposite of one another over the course of approx 12 hours and 28 minutes. Each 12 and 28 minutes the cycle repeats itself , so that the tidal movements advance a little each day.

You can lean more about this setup and ow we did it form your build thread here:
 
OP
JNalley

JNalley

Valuable Member
Review score
+0 /0 /-0
View Badges
Joined
Oct 12, 2021
Messages
1,190
Reaction score
1,548
Review score
+0 /0 /-0
Location
Grandview
that is an odd looking return - is the flow entering through that grate in the middle of the photo?
Yep, and the 4 little holes at the top (which I think are siphon break holes). The tanks overflow, return, and ATO Reservoir occupy the whole back, see here (Blue arrows are return):
1643487915429.png

Fiji makes a decent aquarium, and i believe you are correct, that the larger sizes do have dual return lines - one in each corner. In that setup, the RG is a great choice and can really create soem movement in tank.
Yeah, it's the 81 EXT seen here: https://www.fijicube.com/collection...on-w-external-overflow-rimless-tank-fiji-cube

Definitely dual return, and I agree, if I can't do a tidal system with it the RFG nozzles would probably be great. At least, I hear lots of great things about them.
as far as making tidal flows - this is possible - in fact we do this in our own aquarium her in the office using a dual closed loop setup. our 134-Gallon Cube has two closed loops, each with their own pump. The two loops ramp up and down opposite of one another over the course of approx 12 hours and 28 minutes. Each 12 and 28 minutes the cycle repeats itself , so that the tidal movements advance a little each day.

You can lean more about this setup and ow we did it form your build thread here:
Nice, I'll give it a look over, Sicce's tidal flow is built into the Wifi scheduling of their returns and Xstream Wave Makers... though, I think doing returns in Tidal, and Wavemakers in something like Reef Crest or even a Standing Wave would make for the best representation of currents.
 
Avast
BRS

Peninsula Reef Tanks...

  • I currently have one

    Votes: 80 24.0%
  • I used to have one set up

    Votes: 16 4.8%
  • I would like to try one in the future

    Votes: 169 50.6%
  • No interest

    Votes: 69 20.7%
RED SEA
Top