Protein Skimmer? Fluval U4


Reefing newb
Hi all

I am new here. Used to own a 30 gallon, seahorse only tank, until I found out I was moving across the country and only had it a year. I sold my ponies to a local hobbyist who did some work with corals and seahorses. Everyone was happy and healthy, however, this time I want to go a bit bigger.

I have been in my new place for 2 years so I want to do another seahorse tank.

I have my hands on a 46 gallon bow front with about 35lbs of live rock
I bought the set and it came with a Fluval 302/304 (not exactly sure) and a protein skimmer (away from it right now so not sure on specific brand or model)

Since I am a bit limited on space, I want to replace the current filter with the Fluval U4 which is an underwater 35-65 gallon capacity. Would this be a good idea? I have read some pretty good reviews. It has several settings for water flow, one of which looks like it shouldnt be an issue for the horsies.

Tank is fully cycled and just waiting for some additions.

Also, is it necessary to keep the protein skimmer? It is a bit of an eye sore but if it will make a significant difference then I will be happy to keep it.

I have FINALLY located some so-far-so-good seahorses at a LFS, they are h. erectus and yellow, will be setting up a feeding next week to ensure they are in fact CB. I just want to make sure the tank filter issues are settled before I add them.

I will be going pair by pair, ending with 2-3 pairs.

Any advice would be very appreciated. It has been 2 years so a bit rusty on a bit of the stuff, however it seems to be coming back very well.
Have you ever considered setting up a sump and putting a skimmer down there?
From what I'm seeing just googling that fluval, it looks like a plain old submersible power filter to me. Not really a neccesary thing, especially if you do a sump.
A protein skimmer is way better than a canister or hang-on-back filter. I would forget about the Fluval altogether and just use the protein skimmer. As long as you have live rock, that will be fine for filtration.
I have considered it, but my stand (which is actually a dresser like of thing with a marble top) has no room underneath, just some drawers which are built to never be taken out, because i have considered that too. It has become a part of my living room and I'm in a condo so thats why space is a bit of an issue.
I did begin looking for an aquarium/stand combo I opted to save the $200 on the stand. Now I'm regretting such decision so that's why I've kind of hit a brick wall, a part of me wants to just get a new aquarium and stand, a part of me says who cares.

Thanks for the tips though, and Biff, I had no idea I wouldn't need a filter, I know how much the Live Rock does, but no idea with a protein skimmer a filter wouldn't really be needed.
Yeah, a protein skimmer and 1 to 2 lbs of live rock per gallon is the best filtration system you can have. HOB and canister filters tend to lead to high nitrates if they are not regularly cleaned.
Hey, welcome to the site!

You want to make sure your protein skimmer doesn't blow micro-bubbles into your tank as it may cause trouble with males. Also, you'll need to be sure to provide lots of "hitching-posts" for them to grab on to. Mine love leather corals, sponges and gorgs. You can't add any coral with a sting so you'll stay with mostly softies. You didn't mention your lighting system, what do you have? You're feeding what kind of frozen enriched with vibrance? How do you enrich them? I used to use vibrance but haven't for about a year. I'm doing Rod's, PE mysis and brine shrimp with a bit of freeze-dried plankton added in and my horses colors are doing much better now than with vibrance. Shipping costs for the Vibrance is really high and if you don't enrich properly that stuff will muck up your water really fast. With a 46 gallon, you'll want to have 2 pairs of horses and loose the fluval filter. Can you add a sump?

Welcome aboard! Great to have another pony keeper!

Sorry for the delayed reply,

I decided I want to start new since I have made the costly decision that I don't really like the current tank.

I am considering re-doing the whole thing so I can buy a stand and include a sump.

Right now, I am looking at a 33gal 24" high tank

I still have to take measurements of the stand to see how big of a sump I could include.

My plan is, an overflow, with pvc connecting to the sump,
1st compartment - refugium
2nd compartment - protein skimmer and heater
bubble trap
3rd compartment - return pump

My issues are, making the tank sump ready, drilling etc.
And, building the sump itself.
I think I did find some good links on this forum in regards to building sumps though

Within the tank, I would like about 30lbs of LR, and in the refugium, some macros, sand, and about 10-15lbs more of rock.

My concerns are with the width of the tank, if the rock would take up too much space, like I said, still have to take some more measurements.
When you're taking your measurements for the sump, what a lot of people forget is to measure the opening in your stand also. It doesn't pay to buy the biggest tank that you can fit in your stand if you can't fit it in the doors. Quite a few people have made that mistake here.
24" is fabulous for most species of horses! What is the width of your tank? My 55 is 12 inches and it took a long time to get the rock stack looking good but it can be done. Your plans for the sump sound good but I would post the specifics in the DIY thread to have someone check it before you spend money. What are you doing about lights? If you're setting up now, you're looking at a lot of months before you get horses, you'll want to go through most of your algae cycles before you get them. You want it stable. 33 gallons with a good sized sump you're looking at 2 pairs of horses. Start looking into Macro a great place: <head> <title>Macro Algae : Your Source For Quality Marine Plants and Macroalgae Look into leathers too, horses love to hitch on them. Keep us posted on your progress, how exciting!!!!!