Skimmer placement

In a different thread http://www.3reef.com/cgi-bin/yabb/YaBB.pl?board=Filters;action=display;num=1101444956;start=4#4 we were discussing the positives and negatives of placing skimmers either drawing water from the display tank.

I thought that this would make a good topic for general discussion and I hope you will all contribute your thoughts. My initial post is below for your comment.

John

 

I am all in favour of sumps, in fact IMHO sumps are one of the first things you should consider when setting up a new tank. They hide pumps, heaters etc and give you a greater water capacity, which is a good thing.

You can also include DSB's, algae beds, some more rock, a refugium which are also all good things for water quality.

However, I don't think that it is a good idea to move the mechanical filtration, whether it be protein skimming or a cannister filter to the sump. In all instances I have seen, display tanks are either drilled or have a siphon arrangement which drains the water from the display tank to the sump. It's a good arrangement except for one problem and that is that it drains only the first inch or so of water. So when you feed the fish, or the fish deficates only some of that actually goes into the sump for processing, the rest stays in the display tank and does its thing (yuk). It's true that snails, hermit crabs and other detrivores will eat some of this material, but don't forget that they deficate too. I think it was Dr Shimek who stated that marine organisms only absorb about 20% of what they eat, so as you go down the food chain there will always be some waste that is not processed. For that reason I think a better way to have a sump for water capacity and some chemical filtration, but keep the protein skimming happening in the display tank. Keep the cannister filter for running carbon etc and let that cycle in the sump.

Not sure if I am being very clear above but I hope that you get the gist, and if not I think it would be a good subject to discuss and pull apart.

Now Gator996, I would almost bet you, because of what I wrote above, that if you included a sump in your system right now and moved all the fitration capacity to just cycle the water that was available in the sump, that your water quality would decline.

Having rabbited on for so long, and in answer to your question, IMHO if the filtration you have at the moment is giving you excellent water quality then I would keep the skimmer portion running in the main tank but get that sump and run the cannister in there.

 

As we know, not all tanks/systems created equal. My water circulation, 1,600 gallons per hour +-, keeps the Dissolved Organic Componds suspended in the water and mitigates the fact the my prefilter is only skimmimg the top inch. My skimmer resides in my sump and the skimmate is is no different there than it was when my skimmer was in my display tank.

The skimmed water flows through my refgium wher he macro algeas scrub it of nitrates and phosphates befor bein pumped back to the display tank.

My water quality has improved since I set up my sump/refugium in the configuration I just described.

 

Very interesting. I can see good points and bad point to both setups. If the skimmer is in the main tank, then one doesn't have to worry about chopping up the bugs that so many of us are trying to grow. But you do have to worry about the bubble that could enter into the tank.
Now, if the skimmer is in the sump, you do get to hide it and not worry about bubbles as much. I wonder what others have to say?



phil

 

I'd put the skimmer in the sump too. Since it removes from the water column, then it will do the same in the display or the sump.

In addition I can mechanically remove particles from the water column by employing a HOT fiber filter. A simple mod of a wet/dry HOT filter (remove all except the fiber and perhaps the activated carbon bags) you got one working.

Issues on these such as nitrate production and leeching are easily solved by including the replacement or washing of such fiber every 2-3 days which more or less is the same time you'd check and clean your skimmer. all 5 minutes tops.

Easy and keeps water params good.

 

As an after thought, do you think that it's possible to have the skimmer in the main tank but have its discharge drain to the sump?



phil

 

Very interesting post John! I keep my skimmer in the sump because with all of the circulation that I've got going in my tank, detritus and waste rarely have a chance to settle. That's not to say that keeping a skimmer on your display tank isn't a good idea. In fact, I've seen some set ups that have a skimmer on both the display tank and the sump! I, however, am not that anal

 

This was my Responce from the before thread. It's very early in the morning and I'm not really thinking so I will have to read later

John, Interesting thought, but my question is whether there would be any benifit at all to a skimmer hanging off the main tank versis in the sump. No matter how hard we try the majority of "Waste" is going to end up on the sand or in the rock work and Power head after power head will not keep it suspended either in the first 6" or in the water colum at all. So I don't see the benifit of a skimmer drawning direct from the display area.
In your case I do see huge advantages to Bare bottom tanks with Skimmer intakes at the bottom, but my fear would be sucking in snails or fish. To avoid this you would need a pump pre Filter and this would stop any bigger floating organics from entering your skimmer anyway.


J

 

Just as a clarification as I didn't make it clear in the first instance, I was really talking about taking water from deep in the display tank for processing. I didn't mean that a skimmer should be placed 'in' the tank, nor was I referring to hang on type skimmers and comparing them to in sump type skimmers.

Probably a better example would be this. Lets assume a generic hang on type skimmer, a 50 gallon tank ( drilled or with syphon overflow ) with a 30 gallon sump.

John

 

By allowing the surface water (with it's associated gas exchange) to drain into the sump, you are by default bringing lower water up to the level of the overflow...thereby oxygenating more water, and releasing more waste gases to the surface.
Powerheads located deeper in the tank move bottom detrius and keep it suspended better than a submerged pump drawing water into but not directly circulating the water in the tank. ;D

Especially in the case of bare bottom tanks, you can really blast the bottom of the tank and keep detrius suspended. I have sand, but my powerheads expose glass on the bottom from direct bottom circulation of the powerheads directed towards the bottom of the tank ;D

Of course, this is all My Humble Opinion!