Flow and Floaters

[jameson_uk]

I guess there is no silver bullet but wondering how others balance flow and floaters. I have Sterbai Cory and Rainbowfish who like higher oxygenation levels but the Frogbit doesn't like the increased surface agitation to achieve this...

Since rejigging things a little last week the flow from my filter has gone up a bit and now I have my frogbit being crunched up at one end of the tank.

My spray bar is along the short length of the tank and I have a flow pump at the bottom on the far end. I am wondering about pointing the spray bar under the water and using air stones for surface agitation. I am trying to get a little more flow around the plants in the opposite corner to the flow pump (under the spray bar) as the stems I have there have been struggling.

Tank is low tech so I am not worried about CO2 gassing off.

How are others managing this balancing act?

 

[Hyoscine]

I really don't have a lot of experience, so this might actually be a terrible idea for reasons I hadn't considered, but I found that I had enough flow from my filter to run a short spray bar and a nozzle with a venturi. Takes the flow from the spray bar down a notch, and hopefully oxygenates my tank a litte.

 

[techfool]

I use suction cups (you can get some with a piercing) and string to fence off a section of the tank. The frogbit lives there. It's not where it would end up if left to its own devices so I find it's not too scrunched up. It's growing and putting out new leaves. When I change the water the string is too high so I have to put all the frogbit afterwards.
My frogbit in a no-flow environment is growing much bigger and faster with longer roots. I think frogbit prefers no flow.

 

[zozo]

If it's low tech, you might just have a bit to much flow.. Matter of speaking, for floating plants that is.. Depending on the size of the tank versus stocking a 3 times turnover can be sufficient enough. That's what i have +/-, got a 100 litre tank and a 800 l/h pump, but the head it has to push plus the dirt in the tubes etc, i estimate i at least loose 50%. And according other pumps i have rathed less giving more it's a bummer of a pump not comming up to it's specs. So that leaves me with maybe 3 to 4 times turnover.. Plus a bunch of floating Salvinia, Hygroriza and a lily, never mind the duckweed in it. But i have no issues with these plants cramping up at one end.. Also i do not use a spray bar, used to use a duckbill outlet, but wile ago i took it off and it's now just a pipe. But it's a knee i can turn from left to right. And the water flow is diagonal aimt towards the centre of the front panel. I got the majority of plants floating at the left side of the tank, but also little portions turning circles left and right from the jet of the ouflow.

A also have no other issues at all and see no reason why i should up the flow i see all leaves of all plants regardles where it is slightly wave and dace in the flow.

 

[jameson_uk]

If it's low tech, you might just have a bit to much flow..

I have a 180l tank with a 100l/h rated Eheim filter so about 5.5 times. When I had a fine sponge in the filter this cut it down so flow was probably about 3-4 times anyway. I removed the fine sponge and removed a little bio media which has now increased the flow (cleaning the spray bar also seemed to help a lot ).

A also have no other issues at all and see no reason why i should up the flow i see all leaves of all plants regardles where it is slightly wave and dace in the flow.

This is part of the issue I have and why I have been playing with flow. With this setup there was little movement of plants at the bottom of the tank not detritus. I added the flow pump which solved this but I still have a corner of the tank where the stems show no movement, they aren't doing to well and I get a build up of detritus in the corner.

I guess the flow isn't strong enough to hit the glass on the opposite side, go down to the bottom, back along the substrate and back up the other side. I guess the Frogbit is probably actually reducing the amount of water reaching the far side too.

On top of this I have been struggling with my rainbowfish so had been looking at upping the oxygen levels for them. I do run an airstone off a tiny air pump but I added two more powered by my eheim pump (massively more air). The pH went up by about 0.5 so I guess it did raise oxygen levels. It also seemed to increase flow as the temperature increased by about 0.5 - 0.8C (measured in the opposite corner to the heater) which I guess was actually distributing the heat a little better. Problem with air pumps is they are so damn noisy (I got the eheim as it is meant to be the quietest too)

 

[JMorgan]

Problem with air pumps is they are so damn noisy (I got the eheim as it is meant to be the quietest too)

My seven tanks are all in the same room so I run most of them on air driven filtration running from one of these EV20 - which is an amazingly quiet pump for its power. Even so since its doing the work of the half a dozen plus smaller pumps it replaced (and is much quieter than them collectively though they were Eheim 200's and 400's), I wanted to minimise the noise and I did some experimenting:

My best solution so far is to stand it on a bathroom tile which itself stands on rectangles of sleep mat cut to size. Thats the camping sleep mats that roll up - about £4 from Home Bargains. I use three layers. That's a combination of using extra mass (the tile) with absorption from the mats so that most of the vibration that would otherwise become sound energy is soaked up. I'm stunned by how quiet it is and 20 watts to run all the filtration on six tanks is very welcome too, especially since it could easily do more.

Of course it also runs quite a few air stones and even a slow trickle of air in the right spot or dead spot will move a lot of water upwards and suck it downwards elsewhere. I have frogbit in all my tanks and it generally does OK - I get a lot of lensing holes because of water splashing about so I'll watch this thread with interest. I've played with making loops of air tube to corral it into one place, but as has been said that only works til you change water . . .

 

[BubblingUnder]

Frogbit doesn't like the increased surface agitation

You may be right about the flow. I use an adjustable internal filter in my tank on its slowest flow setting (submerged a couple of inches to reduce surface agitation). When the filter sponge starts to clog my frogbit goes rampant. As the flow increases after cleaning its growth slows. I've considered using a clear sealed airline with pieces of cork to act as a boom tethered to the tank sides with suction cups (similar to Techfools suggestion) but still thinking about it. I removed my smaller Frogbits as they are too mobile but use larger ones roots tethered to shallow plants & houseplant filter roots at the rear of the tank.