TOM's Surface Skimmer usage.

[eric_kclee]

Hi will like to ask some unusual question.

We normally use TOM's surface skimmer by connecting it to the input of a cnister filter right?

In near future when I upgrade my tank to 4ft, I may want to try out something new and need your advice.

I plan to use a sump in the bottom cabinate, I heard (in other thread) most of the sump require a overflow system within the main tank (acting as a skimmer). However this take up quite a bit of space in the main tank and it is not a pleasant view.

Can I just raise a tube near to the water surface and attach TOM's skimmer to the ends? Will the simmer works without a powerful suction effect as in normal usage?

Or can someone advice how this skimmer works, does it need suction forrce to sink the cup and induce the water return?

Thanks.

[nbk3]

skimmer ah , it needs quite abit of suction . But if its based solely on water-levels & gravity , u might need to close off the bottom , and use only the top .

[eric_kclee]

So it can be done huh?

I see people using just a open end tube for water to return to sump, however water level is always changing due to evaporation, so ended up design and put the tube's end way below water surface...this resulted in no skimmer effect.

SO I saw this skimmer from TOM, find it innovative, and feel like attaching it to the Sump Return Tube's end, let the cup be movable and follows the water level. This way it will skim the water right?

Will this work? Thanks

[jacian]

Since the cup is movable and assume it does follow the water level, for the flow to stop, the water level need to fall below the movable cup. That means, it will allow quite a hugh volume of water into the sump and should your return flow fails, will your sump overflow?

[vinz]

No the skimmer will not work. But your overflow is a skimmer.

The most space saving OF I've seen is a single pipe protruding from the bottom of the tank. The top of the pipe is where the water level would be. The pump in the sump pumps water into the main tank, when the water exceeds the height of the pipe, it overflows in.

If you want, you can cut the top of the pipe so it has fingers like the TOM skimmer.

The problem I find with OF systems is that mostly only the top water flows. Detritus at the bottom parts of the tank hardly get sucked out. To get pass this, they install a verticle partition with a opening at the bottom. For planted tanks, this is a bit of a problem because of substrate but it is esily solved. Simply ask the tank maker to put the opening a few inches above the bottom of the tank.

This design, however, negates the skimmer effect as the partition has to be above the water level and the water surface on the main side of the tank won't get skimmed.

[eric_kclee]

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On 8/12/2003 4:58:13 PM

Since the cup is movable and assume it does follow the water level, for the flow to stop, the water level need to fall below the movable cup. That means, it will allow quite a hugh volume of water into the sump and should your return flow fails, will your sump overflow?
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Jacian,
you think it will follow the water level and works like skimmer? Thanks.

On your secod point, I also read about the other thread 'phobia of sump' quite a long discussion.
I once discussed with the tank/sump maker, they say, the sump should design in such a way that.... when pump/power failure, the sump should be large enough to take all the water that flow down from the main tank. (this theory does not apply to other overflow design where the tube make a 'U' turn and siphon water from bottom of the tank.)

[eric_kclee]

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On 8/12/2003 7:58:02 PM

No the skimmer will not work. But your overflow is a skimmer.

The most space saving OF I've seen is a single pipe protruding from the bottom of the tank. The top of the pipe is where the water level would be. The pump in the sump pumps water into the main tank, when the water exceeds the height of the pipe, it overflows in.

If you want, you can cut the top of the pipe so it has fingers like the TOM skimmer.

The problem I find with OF systems is that mostly only the top water flows. Detritus at the bottom parts of the tank hardly get sucked out. To get pass this, they install a verticle partition with a opening at the bottom. For planted tanks, this is a bit of a problem because of substrate but it is esily solved. Simply ask the tank maker to put the opening a few inches above the bottom of the tank.

This design, however, negates the skimmer effect as the partition has to be above the water level and the water surface on the main side of the tank won't get skimmed.
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Hi Vincent,
I saw people did that as you recommended, it ended up the water level is 3-4inch above the pipe (to the sump) and it does not work like skimmer (too deep)

After much thought, I think I know what you mean. I think the missing secret is , the pipe to the sump must be large enough so that flowrate to sump is > than water pumped back to tank. Then it will have skimmer effect, Right? Vincent?


On your second design,
I also saw somebody trying out new design, They do exactly what you describe, then near the water surface, they delibrately open a long slit vertically (~3mm wide, about 10cm long slit), half of the slit above water and half under water. Slit is small so that main water to sump is still from gravel level, then the slit just act as a skimmer.
Sound right? will this work?

[vinz]

Eric, I think you've figure it out.

[eric_kclee]

Vincent,
will the vertical slit design work? your opinion please.

[vinz]

I think it'll work, but not as a skimmer (at least not for the scum), but simply to let scum thru so that they get drained.

I'd be careful about the slit being choked by floating leaves. Perhaps a few slits might be better. Or fashion a pre-trap.

[eric_kclee]

Sorry Vinz, can you explain that part 'work but not as a skimmer, not for scum but can drain scum'

It is so late already, probably I a bit blurr. Can explaint more please?

I thought Skimmer job is to remover surface slime, protein layer and some rotten leaves. Please correct me if I am wrong.

[vinz]

If its a vertical slit, and there is an opening near the gravel level, chances are that the water level on either side of the partition will be the same. I don't think this will create much surface turbulance so the slit will probably not do much to the scum. It will skim the larger stuff like leaves, etc. What happens then is that the surface scum will flow thru the slit and then drain down the OF.

Disclaimer: this is what I envisage in my mind and may not be accurate. Just giving an opinion.