Slowly Planning a 75g Seahorse "Reef" Tank

[MissLissa]

Hello!

I'm planning my first seahorse tank- in fact, my first privately owned saltwater tank- and i could use some guidance.

Before anyone freaks out, while I haven't been doing saltwater for many years, I do have a "lot" of saltwater experience... I work at a BioSci research facility where I maintain tens of thousands of litres of fresh and saltwater aquarium systems. I get to work with aquatic life ranging from tiny copepods to giant cold water skates. I've even cared for seahorses (H. erectus and H. kuda) in 80-100g flow through systems. I really loved working with the seahorses, and I think I'm pretty well set up to care for a pair. I even have functionally unlimited access to high quality lab-grown seahorse food, live and frozen.

Now, since I am used to running tanks of no less than 80g tied into 500-2000g systems, I thought I'd check my plan so far with people who have more experience than I.

I'm currently planning on a custom ~60cm x 60cm x 75cm tank (~75g tall) with a 20G sump, a yet-to-be-determined in-sump skimmer, and a 20G overhead refugium. LR and min 4" DSB. Given this meagre info, would the following make sense:

Possible Verts:
1:1 CB H. erectus (could maybe go 2:2 but I am not super sure I want to squeeze that many in a 75g. I'm used to giving 50g+ per pair. Thoughts?)
1 CB Yellow Assessor
1 CB Mandarin Dragonet (very rarely available in my area; I would prefer 1:1 but will probably only find one if I'm being reasonable.)

My vertebrate requirements:
- Must not pick at seahorses. A certain amount of food competition can be adjusted for but it shouldn't get out of hand.
- Must be captive bred. I'd rather pay 100x more for CB than purchase WC.
- Must be willing to feed on the items I can easily source (frozen and/or live pods, mysis, fish and invert eggs/fry, also possible are BBS and adult brine shrimp)

Possible inverts:
2x CB Peppermint Shrimp (might end up pony food?)
Various Trochus, Nerite, Ceriths, Nass. snails
Tubastrea sp. (Sun Polyp)
Actinodiscus/Discosoma (Mushroom Coral): I find 'shroom species hard to identify and apparently some can have sweepers, so I may not take the risk.
Clavularia sp. (Clove Polyp): not a fan of how crazy fast it can grow, to be honest
Capnella sp (Kenyan Tree)
Sacrophyton elegans (Fiji Leather)
Briareum sp (Corky Finger "Gorg") maaaaybe GSP instead but they can be kind of invasive
Muriceopsis flavida (Purple Plume Gorg)
... Plus several fake sponges or something so the seahorses can hitch on that and give the corals a break now and then.

My requirements for coral are:
1) Cannot have anything to do with palytoxin because I like living
2) Must not sting seahorses, so no sweeper tentacles etc.
3) Must not in any other way be crazy toxic or otherwise be known for serious chemical warfare (though I admit this is somewhat subjective)
4) Preferably be something I've successfully cared for already. I have a lot to learn, there is no need to be bumbling around with the corals, too.
5) Not be wild caught.

...and macroalgae which I haven't even begin researching yet.

I'm used to QT all wet items for a minimum of 12 weeks, as well as a deworm cycle etc for all vertebrates.

 

[vlangel]

Everything looks good to me. One question I have is the DSB in the 75 gallon display or in the fuge? I would hesitate to put a DSB in a seahorse display tank. I love DSBs but seahorses put such a heavy load on their tank that you do not want it to get gunked up. Also seahorses should have a minimum of 10Xs turnovet and 20Xs is better. You don't want flow digging up your sandbed but you do want excess food and particles kept in suspension. It can be a tricky balance. I have my DSB in my fuge.

 

[DanU]

Many of us recommend 1 pair of seahorses for every 25 to 30 gallons. Going with 2 pairs should be fine in the setup.

De-worming should not be necessary with CB seahorses, especially if you are going directly to a breeder. There is no exposure to digeneans and minimal chance for Monogeneans. I applaud your quarantine protocol!

Keep in mind seahorses are not a real reef fish. They are sometimes found near reefs but they greatly prefer to be in or near planted areas. One of the reasons why they are so plentiful in estuaries. They find more food there in the wild. If you setup a tank with macro algae, you will find them in the marco's more often than around the rock. One of the nicest seahorse displays I have ever seen was a 120 gal refugium that was all macros.

You will also find that with a smaller tank, such as the 75 compared to what you are accustomed to working with, the seahorses will do better if you can keep it cooler. Ideally in the mid to lower 70's. The corals will do fine, they will just grow a little bit slower.

The peppermint shrimp should do fine in the tank. Many people do fine with them with their seahorses.

For the protein skimmer, take a peak at the SCA-302. For the money, it is a good performing skimmer. There are better skimmers, but at a much higher price.

I also recommend looking at the variable speed DC pumps for your return pump. They are quiet, pretty much vibration free, low energy use, give off very little heat and adjustable instead of relying solely on ball valves for controlling flow.

I would also consider LED lighting if you aren't already. Low energy draw and again give off minimal heat. Seahorses also seem to color up better under them.

Dan

 

[MissLissa]

I was planning on the DSB (4-6") to be in the 'fuge, with a shallower sand bed (2-3") in the display tank to give more vertical space. It would only be a few inches saved, but I think it would still be worth it, gallon-wise.

I don't have much experience with sand in a marine system and I'm not used to smaller systems at all, so I'm curious: would 20x really be enough to blow sand around after the biofilm kicks in? I was under the impression that 20x was fairly standard and considered moderate flow in smaller marine tanks. I ask because if it's enough to blow around a DSB, it's enough to blow around a shallow one, which would be a concern for sure. The seahorses I cared for previously were all in sterile BB tanks but I'm just not a fan of the aesthetic. I don't think BB is ideal for mandarins, either, from what I understand.

I've always done 5-10%+ daily water changes on my tanks (if they weren't flow-through) so I'm not sure that major build up is going to be much of a problem. I ain't afraid of no turkey baster lol

 

[MissLissa]

Sorry, Dan, missed your reply!

I did read the 30g/pair on this forum, but I wasn't sure if that recommendation was based on living space or bioload and when it comes to bioload I'd rather be conservative than extravagant. I made my proposed stocking list with the assumption the two small non-seahorses would replace the extra pair, though my ideas for appropriate bioload may be painfuly skewed. Most of the fish I work with are in the 3-8ft range and the maths are quite different.

Thanks for the tip on deworming. Everything get dewormed a the lab, pretty much, unless the dewormer is very likely to kill it. I'm a bit fanatical about QT, if I'm honest, and I'd rather QT over the 75 day mark to ensure any lurking nasty is caught. I suppose with a long QT period if I suspect anything nasty I can always deworm at that point. In all honesty, though, I was thinking more of the small fish than the seahorses. I'd rather the fishes not bring anything in that might threaten the ponies.

That's why I want the macros in there- if the seahorses prefer it, I want it. I'm not planning on having much LR in the DT; that's mostly something for the corals to be attached to. The fake sponge things are just insurance since softies are probably not going to like seahorses hanging off them very much, and gorgs won't either. The corals are mostly for me, not the seahorses!

Temperature-wise I'm planning on running 22-23C (72-73F). I specifically picked out corals that are likely to do just fine in cooler temps, as far as my minor experience goes.

I'm glad people have had success with the peppermints! I like the idea of them spawning and having more free food

Thanks for the guidance re: skimmer and return pump- I really appreciate it. I will definitely look those up. I really haven't done much research on brands, etc, as yet since I am still learning basics like "sand yes or sand no?". Having a place to start is great. I'm not really shy about spending money on better quality supplies, as long as better function and longevity is there. I'd rather have the expense upfront than spend $$ now and decide to upgrade to $$$ later, because that means $$$$$ was spent overall instead of just $$$.

I am planning LEDs, actually- it's terribly cold here in the winter, but it's also stinking hot in the summer and cooling a tank is a heck of a lot harder than warming one up. I won't say no to energy savings, either!

 

[vlangel]

I was planning on the DSB (4-6") to be in the 'fuge, with a shallower sand bed (2-3") in the display tank to give more vertical space. It would only be a few inches saved, but I think it would still be worth it, gallon-wise.

I don't have much experience with sand in a marine system and I'm not used to smaller systems at all, so I'm curious: would 20x really be enough to blow sand around after the biofilm kicks in? I was under the impression that 20x was fairly standard and considered moderate flow in smaller marine tanks. I ask because if it's enough to blow around a DSB, it's enough to blow around a shallow one, which would be a concern for sure. The seahorses I cared for previously were all in sterile BB tanks but I'm just not a fan of the aesthetic. I don't think BB is ideal for mandarins, either, from what I understand.

I've always done 5-10%+ daily water changes on my tanks (if they weren't flow-through) so I'm not sure that major build up is going to be much of a problem. I ain't afraid of no turkey baster lol

I am sure that you can direct your return nozzles so that the sand is not blown around, even with a shallow sand bed. I just like to blast the bottom of the tank to keep excess food from settling. I totally understand your feelings of a bb system as I share that sentiment. I only conceded to a bb tank so that I could concentrate on keeping my system as clean as possible for my ponies. I however am keeping 4 ponies in a 56 gallon display with a 20 gallon sump. Your tank and system although small to you is considerably larger than mine and you are planning for less bioload. I at least painted underneathe my display so that it is the color of sand which helped me reconcile with the decision to do bb.

I have the SCA -302 skimmer that Dan mentioned and it does a pretty good job. My one complaint is the pumps don't handle being turned off and on a lot so I do my water changes with the skimmer running by turning down the bubbles. That has worked fine.
I also at Dan's recommendation replaced my ancient reliable 9.5 mag drive pump with a Tunze DC 6000 pump. I do love it for all the reasons Dan mentioned.

 

[DanU]

The stocking density is because of the bioload. Much higher with seahorses compared to regular fish. The mechanics of the maceration process during snicking ejects minute particles into the water column and their lack of a true stomach and fast transit through the digestive tract leads to a lot of inefficiency and extra organic loading. This is combined with the fact that they eat extra to compensate.

I understand the lab protocols. They have a lot to deal with and typically multiple personnel. Usually a lot easier in the personal setup.

Based on your plans posted and comments, I would expect you should do very well!

Dan