Refugium for a planted tank?

[Jordan55]

I have a 25 gallon sea horse/macro tank. About a month ago, I added a 4 gallon HOB refugium to the tank. In the main tank, I have halimeda, caulerpa sert., some sawblade caulerpa, and some codium.

I was curious as to what the effect of planted refugium would do?

In the fuge I have some chaeto and some more sawblade. I noticed after the fuge was set up, I lost a good deal of my caulerpa sert. I have few patches left, but I lost probably over 50%.

I am pretty dumb when it comes to macros/fuges. Macros remove nutrients from the water correct? So if I have a fuge with macros, could that be outliving the macro in the main tank? Like taking in more of the nutrients to live, instead of the macros in the main tank?

I know a fuge on a reef system should be atleast 50% of the main tank to actually do good. I mainly added it to get more water volume.

So is macro in the fuge good or bad? Could it be killing off the caulerpa? Is it doing ANYTHING?

Thanks!

 

[Samala]

If you have them on reverse photoperiods the fuge may help to even out pH swings from the photosynthesis going on by ensuring that its always happening somewhere in the system. You will definitely go through more carbon (either as CO2 or carbonate) and more N and P and all the micronutrients by having plants as your photosynthesizers in both areas.

If you do not have much of a bioload its possible that they are directly competing for nutrients and, if one species becomes dominant, could lead to you losing algae elsewhere in the overall system.

For a seahorse tank have a fuge with some plants isnt a bad idea. Beyond pH leveling (be sure to measure to see if this is actually happening) you are providing copepods and gammarus pods a place to procreate where the SH cant get to them. So, a wee bit extra food for the SH to hunt. They will certainly decimate the populations in the main tank. Extra water space isnt a bad idea either.

If you do not yet have the horses in you might consider getting more nutrients into the tank. If you're skimming, stop, or reduce the time the skimmer is on. You can often get away with just aerating a macroalgae only tank and doing regular water changes instead of skimming. If you're feeding hermits and other life in the tank, bump up food additions slightly and slowly. Those two methods are fairly safe for improving the amount of nutrients in the tank without resorting to chemical means. Besides, it may help you avoid a mini-cycle when the SH go in and start to eat enormous amounts of food (which leads to poo and decomposition and such..)

HTH!
>Sarah

 

[Jordan55]

Thank you for your help!

 

[Jordan55]

Hey Sarah, part two.

I decided to go a little bit more in depth into my investigation. I took my water into my work to get tested yesterday.

My phosphates were at 1 and nitrates were at .4

Is that bad? When it comes to a planted tank, I know jack crap as you can see. I know plants live off nitrates and something with phosphates in there also.

I tested my RO water that I am getting from a grocery store and the phos. tested out at .4!

I am doing weekly, sometimes bi weekly water changes of 3 gallons.

What do you think? Too much N and P?

Thanks!

 

[Samala]

Yes, plants live off of nitrates, phosphates and other sources of nitrogen and phosphorus. They also need a slew of nutrients in smaller amounts, what you often see referred to as micronutrients. And, of course a carbon (alkalinity or dissolved CO2) and a light source.

Now, as far as I know, all the macro and marine plants need more N than P to live and grow and be happy. So your PO4 at 1.0 and NO3 at 0.4 is a little backwards, but I wouldn't stress over it. While PO4 at 1.0 is high, once the macro gets going it should come down quite a bit. When you add the fish to this system the NO3 content should also naturally rise, which again, should be fine with the macro.

The values I like for my tank, and people seem to have luck with are PO4 0.1 and NO3 2.5 - 5ppm.

So, lets see what your stand of macroalgae will do once its in the tank and actively growing. I think you'll find it will quickly pull NO3 to zero and should level the PO4 down a good bit.

Final note: your RO water would ideally have no PO4 in it, but for a planted tank, I'm not sure its a huge issue. Remember, I often use 50/50 RO/tap, though my tap isnt too terrible.

>Sarah