Small local tank?

[elusive_fish]

Hi all,

I had my two little girls (2 and 4 years old) down at the beach the other day making sandcastles when we unearthed some kinda shrimp thingy - about 4cm long, with one large pincer and one small. My girls were absolutely fascinated.

It got me wondering if it were possible to set up some kind of simple marine tank to catch and observe (and maybe keep in the longer term?) locally found marine fish etc. I'm an experienced tropical fresh water fish keeper, but know diddly squat about keeping marine fish. All i know is that they are typically expensive to set up and hard to maintain when small But with that being said, could i use an old aquarium either inside or outside to house something? Even just the crabs that are everywhere in the estuary would be fun.

[spoon]

go for it mate you live quite close to the beach so do regular water changes a skimmer wouldnt be necessary hell i wouldnt even bother with a hydrometer just mark a level on the glass when you first put water in the tank and top up with tap water (salinity levels in estuaries are quite variable , so livestock can handle it) the only thing i can see becoming a problem is the temp getting too high in summer but perhaps you have a cool area in the house or you could use cpu fans to help cool it

[elusive_fish]

I might try something as an experiment, especially while the weather is cooler. But im kinda tempted to convert my 4ft tank that currently houses malawis into something different. I've always been fascinated by rock pools and would love to set up something to catch and observe things from that environment.

The main problem with this idea is warmth. I'd like the tank where I can enjoy it ie the lounge, but my wife always has the heat pump cranked up :roll: And from what I see, chillers are prohibitively expensive.

Are there some iypes of rock pool or coastal creatures that are ok living in room temperature water?

BTW, i figured out what the greebly I dug up was.. apparently its a 'ghost shrimp'. Not the transparent kind, it looked more like this:http://martinsmartwildlife.com/167.htm

[livingart]

pistol shrimp or snapping shrimp?

http://www.google.co.nz/imgres?imgurl=h ... :countryNZ

[toppom]

dont keep them with the glass shrimps - there is only ever one outcome and its not pretty for young girls to watch

[elusive_fish]

I might see if I can find a 3ftish second hand tank to set up a local rock pool tank. I'm not entirely sure where in the house I will put it - need to keep the tank and wife cool :lol:

So a chiller is obviously right out of the question, but would i need some kind of protein skimmer for a tank like this?

What should I use as a substrate? just beach sand?

I've heard cycling a cold water marine tank takes ages - can anyone give me a brief run down of how i would go about it for this project (I'm familiar with it in the tropical fresh capacity)

Its weird how excited i am about doing this!

[spoon]

i wouldnt bother with a skimmer since you live so close to the beach just do regular water changes a decent skimmer will cost heaps and theres no point bothering with a cheap one

as for cycling you can use live rock and let it cycle the key difference is compared to freshwater is that you become more interested in cultivating anerobic bacteria that break down the nitrate. although live rock could also be expensive and if you are prepared to do regular water changes you can keep the nitrates down and not use live rock but just stuff you find at the beach /rockpools etc and just use a regular type of filter for water movement and aeration and mechanical filtration .

a cheap way of cooling is to use fans to increase the evaporation but when you increase the evaporation the water gets saltier quicker this means you will be topping up the tank with freshwater more often to keep the salinity the same . you could just mark a level with a vivid on the tank when you first set it up and keep the water topped up to that or you could get a hydrometer(which isnt terribly accurate and would likely be right out of wack because of the cooler temps) other options include a refractometer (expensive but works well) and an automatic top off system which could either use a small gravity fed ballcock system or more comlex electronic float swithces and pumps.

as for substrate while you could use beach sand it has very little biological capacity perhaps use coral sand which will help with buffering and is also a lot more porous

[puttputt]

I suggest you do it properly, use live rock, get a cheap but effective skimmer, and still do regular water changes.

No skimmer, no live rock, and a nitrate factory for filtration (read canister filter) is not the way to run any salt water tank for any reasonable duration, a week or 2 maybe, but after that??

Just because the animals are free, no reason to subject them to septic conditions.

[carznkats]

I think you need to think about how you are planning to keep your tank cool, because unless it is going to be kept in an airconditioned room, it will get in the high twenties and unless you can change water everyday with fresh cold water you will need a chiller (which running costs are very high!).

Not trying to burst your bubble or anything, but I am telling you from experience and it is not nice watching your local fish suffer with the higher temperatures... I had to end up splashing out and buy a chiller to keep my tank at the right temperature (which is about 200L with the main tank and sump). I had tried everything else too, such as the frozen bottles, small fridge etc and they just can't keep the temperature constant.

Good luck on deciding what you want to do, I would actually say it is cheaper overall to go for tropical saltwater than a temperate tank and there is alot of choice out there, I do recommend using live rock though, and a skimmer if you can afford it. If you can't get live rock you can buy the dry live rock, but it will take several month for it to "cure". More info on how to do a saltwater tank should be in a sticky in this section.

[elusive_fish]

After thinking about what you guys have said, I'm not going to do the rock pool tank. Even though I do live close the beach and could attempt something quick n dirty, id rather do things properly.

The other realisation I've had, and stated by carzkats is that it would actually be cheaper to set up a tropical marine... as its much easier/cheaper to heat than to cool.

I don't mean to spam, but as its no longer about what the topic states I'll start another thread on this thought

Thanks all.

[owen]

I don't like disagreeing with what other people have said in this thread, because I realise they are much more knowledgeable in marine aquaria than me... But it is possible to keep certain local marine creatures in far from ideal conditions. I have kept a small local tank for more than two and a half years with no chiller or filter, just Live rock and water changes. I collected snapping shrimp, glass shrimp, anenomes, snails and crabs from the highest water mark, where the water got above 30c and there was freshwater run-off so the salinity was all over the place. I haven't seen any mortality other than predation(the glass shrimp and pistol shrimp get on fine) and the pistol shrimps and smaller crabs have bred many times over the years.

Heres a thread on my tank if you are interested http://www.aquariacentral.com/forums/showthread.php?t=136377&page=7

[spoon]

owen

elusive_fish has decided to go with tropical marines now but i must say your thread is very awesome , i have come across it before and its a very creative idea! is it still running?

[owen]

Ah ok. I just wanted to say that it is possible to keep a local tank long term with minimal equipment, but the potential livestock is much more limited.

The tank is still running. I'm planning on upgrading to a larger more sophisticated tank in the future, as the crab will probably outgrow the current tank by summer.