FieldsOfGreenSeaTurtles

im window shopping for SW tanks right now. not sure if i can afford it right now. with all the technical equipment used in SW i wonder how much is actually needed. i notice that in my reading up online about how to keep a SW tank the literature reads more like an instruction manual of how to put all the usually used equipment together rather than explain the chemistry/biology/ecology behind the equipment. i am wondering if perhaps more information about the science of SW tank systems was known more people could understand them in a way comparable to how many members of this forum understand freshwater planted ecology thanks to Diana Walstad and her book. and then perhaps we could have a version of SW tanks that would be much cheaper than they are now. what the high tech planted tank is to a walstad tank can be what a traditional SW tank is now to what an el natural SW tank maybe can be in the future.

PaulG

I had a lengthy conversation on another forum about this as I had the same idea, but little knowledge of SW tanks back then.

Essentially, you could have a tank filtered purely by water movement and have enough bacteria in the tank, substrate etc to maintain a small bio load and avoid ammonia/nitrite but there's nothing you could really add to keep nitrates down other than water changes. There's not much in the way of nitrate removing flora for SW tanks.

SW tanks can be inexpensive, but if you want to go low maintenance you need to invest in fancy products. If you want to go cheap it will generally be more maintenance. It can be (fairly) cheap if you want it to be, just run the same setup as FW aquarium but with salt water and keep up on the water changes.

mariannep

Your question reminds of the book "Dynamic Aquaria" which is cited by Walstad and which led me to having something very similar to an el-natural tank many years ago. The book actually has more stuff on saltwater than freshwater.
In it they talk about different set-ups, from normal sized reef aquariums to huge public display tanks. Basically what they use to balance their systems is what they call an "Algal turf scrubber" (or close to that). They pump water out into a smaller tank (can be placed underneath where they grow algae), then it's pumped back. The scrubber tank must have powerful lights to keep production going. You then remove algae periodically to remove excess nutrients from the system, much like with plants in Walstad-style tanks.
They also have a neat low-tech idea for simulating waves.

And lots of info on ecosystems and the different creatures that grow in this or that.

The book is: Dynamic Aquaria: Building Living Ecosystems
Authors: Adey and Loveland

Hope that helps!

bortass

It depends on what you mean by el natural. Most of the equipment is for reef tanks, which I assume is not what you are trying to do.

I had a low maintainance SW tank for a number of years. I found it was easier to take care of than my crowded FW tank.

My SW tank had an external overflow to get water to the sump. A protein skimmer, return pump, 2 powerheads in tank, a heater, and lights. I eventually added a larger refugium to the side. So not alot of equipment.

I had alot of live rock and a deep sand bed, probably 3 - 4 inches of sand and only a few fish in a 120 gal tank.

The rock and sand will do the biological filtering. It also provides places for diverse life that hitchhikes in. I went with rock that was not cured first. So I had alot of hitchikers, most good, some bad. I wanted the diversity though.

The lights just need to be enough to see the fish unless you plan to keep corals or algae in the tank.

I would definately have a good protein skimmer to take care the other filtration.

Some of the common pieces of equipment are:
Chiller because the lights cause so much heat.
Calcium reactor because you are growing corals under high light conditions, namely stony corals. Kinda the same thing as CO2 reactors in a planted tank.

So yes I think you can do it but it's all going to be driven by the look you want and what you plan to keep. Will it be cheap? Doubt it, live rock is not cheap but it's probably the most important thing to have next to salt water. You can make your own dead LR, search the net but you really want as much that is live as you can. That's how you get biodiversity and alot of the smaller critters that help keep the tank balanced etc.

Just my opionion.

dwalstad

There are intrinsic problems with applying my methods to SW tanks:

First, there are not that many saltwater aquatic plants, so there are not a whole lot of plant species to choose from.

Second, the high concentration of sulfates in seawater precludes using organic and potting soils (bacteria in these highly anaerobic soils will quickly convert the sulfates to toxic H2S). Thus, I would only use mineral soils with very little organic matter.

Third, I suspect that many SW fish and plants would be inhibited by the high concentrations of DOC (dissolved organic carbon) and humus common to freshwater ecosystems. They might not do well in an El Natural-style tank.

However, I have not tested this. It remains for someone else to pursue this.

Rtifs

I had thought about this. You might try a ‘flats’ type of tank. I’m thinking of South Florida type of setup. Hot shallow water with a grass bed and intense light. What type of fish were you thinking about? In this setup I would try pinfish to start. They are wild, but small enough for an aquarium, pretty and thrive in this environment.

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aquaman555

I would agree with what bortass stated.

Many reef tanks are very natural with minimal equipment. Live rock, refugium and starting with live sand are some natural means of filtration right there.

In my 55g Reef I had 260w PC, kept LPS, softies & zoas. I started with live sand and live rock, couple power heads for extra water movement in the tank. Underneath I had a sump with nothing more than a protein skimmer and refugium. Not what you would call the Walstad method, but reef tanks or FOWLR tanks can be very natural and provide excellent filtration through live rock. Protein skimmers are very important IMO and many people will tell you to always go up a size on your protein skimmer.

As dwalstad mentioned there are few saltwater plants available and obviously corals do not feed through the sand bed as plants would.

aquatic tuna

This method used for saltwater may mimic "el-natural" in some ways ....

http://www.ecosystemaquarium.com/pro...ine/miraclemud

ecotanker

FieldsOfGreenSeaTurtles,

I would second what mariannep said about reading "Dynamic Aquaria". I am in the same situation as you looking to start a salt water tank up again, after a long break. After doing research on the latest tech with SW tanks, I came across the algae scrubber site http://www.algaescrubber.net/ which explains the concept of the algae scrubber in easy to understand bits and gives plans and tips on building your own. Many of the SW tanks by people on that site just use an algae scrubber, with live rocks as their filtration system. One such tank can be found here http://algaescrubber.net/forums/show...s-120-ATS-only.

Some people even have use this concept on FW discuss system with great success.
Hope this helps.

Markv

Low tech saltwater tanks are certainly doable. I don't care to call it el natural, for many reasons. But the idea of relying on plants/algae to keep nitrogenous waste in check along with bacteria is certainly something that works in the salt realm. I have a 'high-tech' reef in the main living space of my house, but keep an extremely low tech marine planted reef in my home office. It's in the basement of the house, and needs to survive occasional bouts of neglect. It basically runs on two pumps, a bag of carbon, heater, and light. The deep sand bed, live rock, and corals play a part in maintaining water quality. But bacteria is your biggest contributor. Denitrifying bacteria are easy to foster in a saltwater tank. I do a water change maybe once a year.

Someone mentioned that there isn't enough plant options to mimic a freshwater el natural. I disagree. While there are mangroves and seagrasses representing true plants, there are a ton of desirable algae to use as well. There are even quite a few red macroalgae that provide nice coloration.

My tank isn't anything special, but it's very low maintenance and stable:





I'm not sure on the rules about posting links to other sites. If it's not acceptable, I apologize and feel free to remove. But here's a writeup on my low tech tank:

http://reefbuilders.com/2011/09/15/simple-reef-tank/

And here's a short blog I did with some neat marine planted tank pics:

http://reefbuilders.com/2011/12/20/marine-planted-tank/

As far as marine plant options, there's quite a variety:

Here's halophila


This site has a lot of macroalgae to show:
http://live-plants.com/