Spraybar and skimmer inlet

Andrew Butler

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I've read in a few places about weirs and spraybars not being effective so I assume that would rule out using a spraybar and a skimmer inlet too? - anyone any experience or ideas to offer?
Andrew
 

ian_m

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I've read in a few places about weirs and spraybars not being effective so I assume that would rule out using a spraybar and a skimmer inlet too? - anyone any experience or ideas to offer?
Andrew
Not too sure where you have got these kind of half truths from ?

A spray bar, positioned slight below the surface of the water, is one on the most excellent ways of getting decent water flow and distribution around the whole of a tank. This is even more so if you are injecting CO2 via an inline CO2 atomiser, allowing you to easily achieve the rough rule of thumb, for CO2 injected tanks of filtration rate being 10 times per hour the tank volume. ie tank volume of 100litres will need a 1000litre/hour filter. Also allowing slight surface ripple allows oxygen exchange into the water, but with slight minus of degassing CO2.

The issue with skimmer inlets in CO2 injected tanks is the falling/splashing water in the inlet rapidly degasses and CO2 you have spent all that effort injecting into the water. It can be done, by having monsterous CO2 injection rate to offset the losses but really is not recommended.
 

Andrew Butler

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Not too sure where you have got these kind of half truths from ?

A spray bar, positioned slight below the surface of the water, is one on the most excellent ways of getting decent water flow and distribution around the whole of a tank. This is even more so if you are injecting CO2 via an inline CO2 atomiser, allowing you to easily achieve the rough rule of thumb, for CO2 injected tanks of filtration rate being 10 times per hour the tank volume. ie tank volume of 100litres will need a 1000litre/hour filter. Also allowing slight surface ripple allows oxygen exchange into the water, but with slight minus of degassing CO2.

The issue with skimmer inlets in CO2 injected tanks is the falling/splashing water in the inlet rapidly degasses and CO2 you have spent all that effort injecting into the water. It can be done, by having monsterous CO2 injection rate to offset the losses but really is not recommended.
I'm a lover of spraybars but also don't like the surface film that accumulates without the use of a skimmer and the 'fashion' at the minute seems to be combined skimmers/intakes which I have tried and do like but I've never tried one with a spraybar as I read about spraybars and weirs not working together so assumed it would be the same with skimmer inlets- I will have to hunt the threads out.
 

ian_m

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I'm a lover of spraybars but also don't like the surface film that accumulates without the use of a skimmer
I don't get a surface film.

Usually a surface film is an strong indication something is out of balance in the tank. Surface film can occur in new tanks as plants/water/substrate "settles down" and in mature tanks is a sign plants are suffering releasing organics (oil) into the water.

You need to treat the cause rather than the symptoms. Possibly poor CO2 flow and distribution, too much light for CO2/fertiliser levels, something missing from fertiliser, new plants adjusting to new environment, dirty filter, without knowing more details of your tank and its setup it is hard to recommend a course of action.

Another way to get rid of surface scum is use an air stone & air pump which will agitate the surface and get rid of any surface film. If using CO2 this can be run outside of CO2 hours of course.
 

Andrew Butler

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Usually a surface film is an strong indication something is out of balance in the tank.
I will have to look these posts up but I know I've read many times about a surface film being the normal.
It is very dry/static like in my room and dust seems to appear from nowhere, not an excuse - just possible reason?
My setup isn't currently running so I'm unable to give you any pics or further info.
 
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I use to have a lot of trouble with surface film on one of my old Aquariums. I put it down to the oils in the fish food. Not much you can do about that if you have fish, they have to eat.

Many people have problems with surface film, I guess that’s why there are lots of surface skimmers available out there.

I would think that any large disruption of the water surface either by it going into the filter via a weir or out of the filter, say with a spray bar above the surface, will cause loss of CO2?

I think a small skimmer should solve your surface film problem. As others have said, you can use a skimmer permanently on say a canister filter inlet or you could use something like the self contained Eheim unit as required?

https://www.swelluk.com/eheim-skim-...MIpsDorIOR4gIVZrvtCh1PhQFeEAQYAiABEgI6OvD_BwE

There are other options out there if you look around. Good luck, let us know how you get on.
 

Andrew Butler

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I use to have a lot of trouble with surface film on one of my old Aquariums. I put it down to the oils in the fish food. Not much you can do about that if you have fish, they have to eat.

Many people have problems with surface film, I guess that’s why there are lots of surface skimmers available out there.

I would think that any large disruption of the water surface either by it going into the filter via a weir or out of the filter, say with a spray bar above the surface, will cause loss of CO2?

I think a small skimmer should solve your surface film problem. As others have said, you can use a skimmer permanently on say a canister filter inlet or you could use something like the self contained Eheim unit as required?

https://www.swelluk.com/eheim-skim-...MIpsDorIOR4gIVZrvtCh1PhQFeEAQYAiABEgI6OvD_BwE

There are other options out there if you look around. Good luck, let us know how you get on.
Thanks for the advice, I used to run the little Eheim skimmers on a timer but I'm just trying to cut down on things in my aquarium with that regard.
 

jaypeecee

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Usually a surface film is an strong indication something is out of balance in the tank.

You need to treat the cause rather than the symptoms.

Another way to get rid of surface scum is use an air stone & air pump which will agitate the surface and get rid of any surface film.
Hi Ian,

I (sort of) agree with the first two sentences above. But, in the following thread, I have been trying to determine the cause of a surface film that I currently have. And I have spent a lot of time on this but I'm running out of ideas/things to try. That's not to say that I've given up - not my style! Here's the thread:

https://www.ukaps.org/forum/threads/does-ferrous-gluconate-cause-a-water-surface-film.58550/

I currently have a lot of surface agitation but it's not making one iota of difference to the oily film. I have CO2 injection. I keep dissolved organics to a minimum by the use of Seachem Renew in my external filter. I am now trying to find a suitable surface skimmer. Do you know of any?

JPC
 

Andrew Butler

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@jaypeecee I'm not saying @ian_m is wrong by a long way but it seems many people run a surface skimmer of some description, Aquarium Gardens and Filipe Oliviera included. Along with the product being manufactured this tells me they are something.

There are loads to choose from and the first things to decide is whether you want to use an electric one in addition to your current filtration or one which works as a skimmer inlet to your filter assuming you have an external filter. There's benefits and negatives to both sides.
 
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I don’t believe there is anything inherently wrong with my 37L Nano at the moment but I still have surface film. Luckily not enough that I need a skimmer. I’m pretty sure the cause is the large piece of bogwood in my tank and I’m not about to remove that.
 

jaypeecee

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@jaypeecee I'm not saying @ian_m is wrong by a long way but it seems many people run a surface skimmer of some description, Aquarium Gardens and Filipe Oliviera included. Along with the product being manufactured this tells me they are something.

There are loads to choose from and the first things to decide is whether you want to use an electric one in addition to your current filtration or one which works as a skimmer inlet to your filter assuming you have an external filter. There's benefits and negatives to both sides.
Hi Andrew,

I've decided to buy the Eheim skim350. On the whole, the reviews are good. But, several people comment that it can suck in fish and shrimps. I am hoping that my tea-strainer mesh will fix that. I think Eheim's design engineers overlooked the obvious here - my guess is that they don't keep fish themselves! Although Eheim is a reputable name, they are certainly capable of designing and producing goods that leave a lot to be desired.

JPC
 

jaypeecee

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Many people have problems with surface film, I guess that’s why there are lots of surface skimmers available out there.

I think a small skimmer should solve your surface film problem. As others have said, you can use a skimmer permanently on say a canister filter inlet or you could use something like the self contained Eheim unit as required?

There are other options out there if you look around. Good luck, let us know how you get on.
Hi Aqua S.

Thanks for your feedback.

See my reply to Andrew above.

JPC
 

jaypeecee

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I don’t believe there is anything inherently wrong with my 37L Nano at the moment but I still have surface film. Luckily not enough that I need a skimmer. I’m pretty sure the cause is the large piece of bogwood in my tank and I’m not about to remove that.
Me again!

I don't blame you for not wanting to remove the bogwood - particularly if you have wood-grazing fish and/or snails.

As I said elsewhere, my concern is that CO2 concentration can rise to in excess of 30ppm as the CO2 bubbles get trapped underneath the surface film. But, to make matters worse, atmospheric oxygen may be prevented from entering the water. I accept that some oxygen will enter the water at the point(s) where water from an external filter returns to the tank. But, using my modified pH electrode, I have seen CO2 measurements in excess of 30ppm. I described this modified pH electrode on another thread.

JPC
 
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I’m not injecting CO2 and I have a Mini Oxydator for the shrimp as many seem to think they’re a good idea.

I do however do a manual film removal when I think it needs it.
 

Andrew Butler

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I have a Mini Oxydator
Sorry to hijack the thread but care to share any more detail of them? Is it something that does a similar thing to a steriliser? (Twinstar etc)
Hi Andrew,

I've decided to buy the Eheim skim350. On the whole, the reviews are good. But, several people comment that it can suck in fish and shrimps. I am hoping that my tea-strainer mesh will fix that. I think Eheim's design engineers overlooked the obvious here - my guess is that they don't keep fish themselves! Although Eheim is a reputable name, they are certainly capable of designing and producing goods that leave a lot to be desired.

JPC
I've a couple I have used in the past and they do work fine, just a bit of an eyesore maybe which is possibly part of what you mean - even making them black would be a positive in my opinion.
There's ways to stop livestock entering as you say, I got some 'samples' of a plastic mesh in various sizes - I can't remember where now though, something you think would be thought through but clearly isn't.
Unsure if/how it will effect your main aquarium flow but I ran one on a timer so there were around 4 on/off stints throughout the day which worked quite well.
 

Andrew Butler

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I really couldn’t say Andrew. I had a large Oxydator in one of my tanks many years ago and I think it did a good job of adding additional Oxygen to the water. I only have shrimp in my Nano at the moment and couldn’t help noticing that many shrimp keepers use them so I thought I’d give it a try. The Mini isn’t expensive and I’ve always got 12% H2O2 on hand for other uses so it’s no problem diluting some for use in the Oxydator.
 

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