Running 2 Skimmers

GeoSquid · Jan 18, 2022

I have a DIY Skimmer that has been producing about a cup of pretty dark skimmate every 4 days or so in my 180 gal. I wasn't sure if it was skimming all it could be, so added another skimmer (Same design) and ran if for a couple weeks. I noticed my first skimmer dripped its production probably in half and the new one wasn't producing all that much. I took the second one off line and the first one is producing back to normal. Would this mean my first skimmer is skimming most everything that could be skimmed? Anyone try two skimmers with success?

Jekyl · Jan 18, 2022

There's no reason for it if you have one that is appropriately sized.

YOYOYOReefer · Jan 18, 2022

no reason you cant run dual skimmers.
most likely you will notice one does most of the work

jda · Jan 18, 2022

This is complicated. If your organics are low, then you might see a drop off of the production of the first skimmer by adding a second skimmer. If your DOCs are high and your current skimmer is not able to keep up, then multiples can work well.

I run multiples and each of them collects nasty, thick skim mate. I also have a ton of fish and feed a lot. With three skimmers, my fuge and chaeto can keep P down to where I like it, but if I just had one skimmer, I would need to use some GFO too.

C_AWOL · Jan 18, 2022

Two skimmers might work well on a high organics system but thats essentially the only situation. Assuming theyre both extremely effecient, youre likely to run into the issue you noticed where neither works.

GeoSquid · Jan 18, 2022

Thank you all for the input. As it is a DIY skimmer, sizing was questionable. I have a 180 gallon tank with lots of soft coral and 3 triggers, hippo tang, fiji puffer, wrass and 4 clowns. I also run a fuge with lots of macro. I was starting to get some decent brown hair algae in spots so thought I would upgrade some filtration, but based on my skimmate it didn't seem like it was helping. The skimmer is a 3" dia PVC that is 28" Tall. The second one was the same size.

YOYOYOReefer · Jan 18, 2022

your second skimmer might need a few days to develop a slime coat and start producing, most times a new skimmer will not perform well till it breaks in (surface oils off the plastics etc)

GeoSquid · Jan 18, 2022

YOYOYOReefer said:
your second skimmer might need a few days to develop a slime coat and start producing, most times a new skimmer will not perform well till it breaks in (surface oils off the plastics etc)

I ran it for two weeks before taking it back offline. How long does the slime coat take? I still have the second skimmer in the tank but it's just sitting there.

G Santana · Jan 18, 2022

I run a skimmer on my 130 with a light fish load and I pull 1 full cup a week consistantly

GeoSquid · Jan 19, 2022

This is about 4 days worth of skimmate from the first skimmer without the second one online. It's probably a 1.5 cups and the color of a nice Guinness! Is this good production for pretty heavily stocked 180 gal? I've never owned a commercial store bought skimmer.

YOYOYOReefer · Jan 19, 2022

depends on your display tank and how much and what your feeding as to skimmate color
as far as why #1 is outperforming #2, try running just #2 for 4 days and compare to this picture

YOYOYOReefer · Jan 19, 2022

are you using airstones or a venturi or how are you getting your bubbles?
might try making it taller. I have a 5 foot diy air driven skimmer that cost less than $20 with a $60 air pump that will beat anyting new for under $500 hands down (if you have the room for it)

not much to a skimmer besides a tube and some bubbles.

GeoSquid · Jan 19, 2022

YOYOYOReefer said:
are you using airstones or a venturi or how are you getting your bubbles?
might try making it taller. I have a 5 foot diy air driven skimmer that cost less than $20 with a $60 air pump that will beat anyting new for under $500 hands down (if you have the room for it)

not much to a skimmer besides a tube and some bubbles.

The first one I built was a counter driven airstone skimmer. It worked great but I got tired of replacing the air stones and the air pumps kept breaking after a short period of time. Now, I have a 600 gph $20 pond pump with a $10 fertilizer venturi going into a 3" ABS pipe that is about 28" tall.

jda · Jan 20, 2022

Here is what my third skimmer produces on one of my tanks... about a week's worth of work and it drains about 32 ounces into a collection container. I consider this the third most efficient one, but it is still good. Multiple skimmers works for me.