Skimmer Calibration

[Brian Prestwood]

I thought it might be interesting to hear how everyone else in MARS calibrates their skimmers.

Skimmers typically have one or more of the following three adjustements...

1. Air valve to control how much air gets into the skimmer.

2. Riser adjustment to control how high the water rises in the skimmer before it flows out.

3. Water valve to adjust how fast the water flows through the skimmer to the tank (recirc skimmers only).

FYI - the plug and play skimmers typically fix (no adjustment) all three adjustments.

The dirtier the water is the weaker (lower air flow, lower water flow and/or water height) the skimming has to be to avoid runny skimmate. In other words, "The enemy gets a vote too." You may have to start with very weak skimming to get avoid runny skimmate.

I use the "no flooding" rule of skimmer calibration. Flooding is when a skimmer rapidly fills the skimmate container and dumps skimmate back into the tank.

I try to find a setting that pushes dry skimmate to the top of the throat but not over under normal loads. When the load is heavy (e.g. after feeding) the skimmate is pushed over. I prefer to start with maximum water flow, air flow and minimum water height. In other words, open the water and air values up and keep lowering the water level in the skimmer until I get dry skimmate at the top of the throat most of the time.

Once I've got a stable setting with no flooding for a week or two I'm tempated to start increasing the strength of the skimming by increasing the water column height. This, in turn, produces cleaner and cleaner water in my tank. Of course, if my skimmer is tuned to very clean water then even small introductions of "dirt" can cause flooding.

So, how do you calibrate your skimmer?

 

[dots]

I have a Euroreef RS6-1 in-sump skimmer, not inline so no gate valve mod.....I don't have the newer one with the air line valve, but have been meaning to do that. I am interested in some of the mods to get mine fully optimized, but hadn't researched it yet. (Off topic, Ost has some skimmers there, where I got mine last year, did you guys know that the dash series that they advertise and sell there are a discontinued series? They should update that sign big time and get some new ones on display. I found Exotics new case very cool the other day).........

I tend to do the same as you Brian, no flooding.....it sucks to have some in there and have it flow back in because of a SNAFU......I like to adjust mine so the foam starts at the bottom of the cup, bubbles up into the cup rather than on the inside of the barrel on the way into the cup. I prefer a "dryer" skimmate, and mine isn't loaded that heavy ever so I don't produce much......

Compared to other hardcore SPSers, I may have a "small" skimmer and is rated for 100g rather double my volume.

 

[Brian Prestwood]

Doug

So no air value to adjust air. I'm guessing you have a riser height adjustment. Correct? Is that how do you control the thickness of the skimate?

 

[Avalanche Wolf]

On m CA super vortex 1002 skimmer it only has a riser height adj.

I place it right at e base of the collection cup. Give it a dark green skim b can still see through it.

sorry typos , low bat on wireless

 

[robertloop]

I have a top fathom skimmer. The 100.

It has air adjust and water hieght adjust. I am running an 802 hagen pump on it. I run everything at full blast all the time. When I first set it up I throttled it back by lowering the water level in the skimmer. Now I just run the unit on full all the time and it skimms pretty dense skimate. Not very much however. Thats why I think I need a better skimmer. Other wise I would wet skim all the time. Just enough not to flood... and probably just tweak the water height to attain the level of skim.

 

[dots]

Thickness.......not much, but yes has the riser tube, where the level of the sump has a direct corelation to that.

I added some of those tigger pods, will those suckers proliferate in our tanks?, so I took out the sock and skimmer for a few days.....

I just cleaned the cup and had a nice buildup on the inside of the chamber before the overflow into the cup...which is usually where a lot end up. I try to make it add to the cup slow enough to where the water evaps over the day and I don't have to change it as much.....thats about the control I have over the "thickness".....I can either change the cup more or less and let the water evap out of it......performance is about the same either way.


Think the air valve would help, I know there is a "club" on the filtration forum that mods these all the time, but hadn't......Until I had gotten my plumbing setup finalized, I was going to redo everything more permanant...and that was on the list.

Would help to turn down the air when the skimmer "goes crazy"

 

[Brian Prestwood]

RobertLoop

"Other wise I would wet skim all the time."

Ah, the fast and loose approach to skimmer calibration. That's a tougher ballance. In my experience, you can't go to far into the wet end of the skimmate thickness range before normal activities (e.g. feeding) will cause flooding. Not that I don't try.

ORP is inversely proportional to disolved organic compounds (DOCs). As DOCs go up ORP goes down. 350 to 390 is good. 300 is too low.

Here's how I believe ORP affect skimmate thickness...

Skimmer setting that produce dry skimmate at an ORP of 390 (clean) will produce wet skimmate at an ORP of 300 (dirty). In other words, the DOCs gets a say in what skimmer settings produce dry or wet skimmate. I may have the numbers wrong but I beleive the relationship is correct.

pH affects the thickness too. I don't have a good handle on it. It seems like the range my tank pH cycles in (8.1 to 8.3) doesn't affect the thickness much.

So, if you're increasing the strength of your skimming (tuning toward the wet side) eventually you'll get to a point where a normal increase in the DOCs causes flooding.

 

[robertloop]

fast and loose....... :lol:

I've been blamed for that on more than one occasion!..

Either way, my skimmer is rated for "up to" 100g. My tank is a 120 plus the 20g sump. I was on Topfathom's web site the other day and it looks like I am using an underrated pump. It recommends a mag 5. I may try that before buying into another unit.

 

[Brian Prestwood]

Stable fast and loose is a good thing on skimmers. Yeah, kick that pump up.