wet or dry skimmate?

I have been running the Remora AquaC for about a month now on a 20 gallon tank with a 10 gallon sump, and it is working really well.

At first I was getting a very frothy/foamy dry skimmate with the collection cup as low as it could go. Recently, it switched to much wetter skimmate, it came out like tea water. So I raised the collection cup up about 1/2" and I am now back to the foamy stuff.

I have two questions:

1) Why would the consistency of the skimmate change without changing the height of the cup?

2) should I stick with a dry skimmate? What is better?

thanks

 

The skimmate properties could change because the skimmer is breaking in or due to the chemistry of your water. Most new skimmers tend to have oils leftover from the manufacturing process that make them skim less effectively at first. Also, if your water is getting cleaner, or dirtier, that could effect the performance.

As to wet or dry, this is a big debate. I think dry tends to be a bit more consistent, sometimes chemicals can make a skimmer go crazy, so, if that happens and your already running wet, now you may be running really wet. Also, removing more water can result in changes in salinity as your ATO (or you manually; if you don't have an ATO) adds water back.

On the other hand, skimming wet may help ensure that you get as much out of the water is your skimmer is capable of collecting. There seems to be a point though, were you are removing as much as the skimmer is really capable of. It's not clear that you need to skim wet to get to this point.

 

Thanks for the info +k!

I think I will stick to the dry for now because I want to avoid drawing too much water out.

As for the change, can a transition to a wet skimmate indicate a cleaner or dirtier tank? Has this been investigated and can it be used as a rough guide for water quality changes?

 

No, not really, that was just an example. A lot of things can effect skimmate, making predictions would be tricky and probably unreliable. Certain chemicals can make a skimmer go crazy, so, if something is n the air and gets into the tank, or you use epoxy to glue something etc... Also, some skimmers may be working close to capacity, so, there is just no room to remove more.

Here are some good skimmer references though:
Skimming Basics 101: Understanding Your Skimmer by Frank Marini, Ph.D. - Reefkeeping.com

What is Skimming? by Randy Holmes-Farley - Reefkeeping.com