elusive_fish

Hi all, it has been a while since I've been around. The last time I had a functioning marine aquarium was February 22, 2011. I'm sure you can figure out the rest of the details So I've always been fascinated by rock/tide pools and the amazing creatures within. Now that I have two little kids I'd love to be able to set up a tank that we could collect, study and look after some of these things in. I have a bunch of questions I'm hoping the wise people around here can help me with: 1/ My initial thinking was to keep a relatively low water level - say 6" - which also happens to work well in an area that tends to randomly slop water eveywhere. Then have maybe a third at one end set up so that it is out of the water, in order to have a place where estuary crabs could get out of the water. But I'm not even sure they would, seeing as its normally the water that comes and goes, not the crab. Would this be necessary/useful? 2/ If I used 'live' sand, natural sea water and some rocks from a tidal area, would the aquarium cycle still take months? 3/ I don't have, and don't ever plan to have, a chiller. I know the local stuff likes it colder, but surely tidal creatures can tolerate temperature extremes better? Some of the pools get quite warm after spending hours in the sun. 4/ What are some things I should and shouldnt keep? I saw a small octopos in one of the time pools once and would LOVE to keep one of those... but I know they have have very specific requirements and tend to grow large. Triplefins? Catseye snails? Anenomes? Amphipods and copepods? Crabs? starfish? Any suggestions or insights are appreciated. Ben

I'm glad you managed to sort things. My marine fish are sitting in my unheated, half empty tank. They are probably dead by now :tears: I feel so bad leaving them, but i didnt know anyone/anywhere I could take them. We're not getting power and water back for days. Our family left to Hanmer springs so that we can have a shower and power to contact people

It's a minor piece of happiness to know someone remembered me! My immediate family are OK, but my parents house is gone for sure this time. Our house now has a hill in the hallway you need to climb to get to the bathroom. The place was absolutely ransacked, with the entire contents of our kitchen on the ground. Somehow my fish tank survived the shake, despite all my coral rock arrangement collapsing. I must have had 50L of water on the floor. All fish are/were alive, but we've since left Christchurch as apparently it will be days to weeks before we get power back. Drinkable water might be longer. I tried to call pet places to take my 6 marine fish, but i couldnt get hold of anyone and they probably have problems of their own. They will be no doubt deceased by the time I get back. I think this will be the end of fish keeping for me. My business is damaged to an undetermined level at the moment. I barely avoided being hit by our commercial oven and an avalance of crockery. I gave away hundreds of dollars of milk and food today, as it will spoil in the next few days if I didnt find homes for it. I made sure the local firefighters were getting very well fed, as well as a backpackers hostel around the corner from my cafe. If we can't open our business for a few weeks this could mean absolute financial ruin for me and the family. I may just have a possible out by taking a job for someone else... depending on whether their business is operable or not. But my family are safe, and that is the only thing that truely matters. I hope all in Christchurch are well and that loved ones are all accounted for. I really don't know how the city is going to bounce back from this... broken houses, people and roads are going to be a ubiqitous sight for the next couple of years.

Man, rock pools are FASCINATING places. I now have 3 catseye snails and 4 ghost shrimp and one limpet that had a cool looking piece of macro algae growing off his back in my tank. All look happy at this stage. The shrimp dont seem to like the strong current so much, but they look to be forraging around. The triplefin I caught last time gorged on the copepods I put in. Looking very fat and happy with himself now. I saw an awesome little octopus and was just blown away by his ability to almost instantly change colours. Black, orange, redish, grey. He was in a shallow wide pool and just kinda backed away from us, keeping his eyes on us the whole time. Even shot some ink. I was tempted to catch him, but i know he wouldnt last well at home. Pity really, what an amazing thing to watch!

I had an incident with my new tank involving a brass gate valve and im still not sure if my tank is polluted as such. All parameters look fine, including copper levels. But I don't have a way to test for potential zinc pollution. Rather than test with something tropical (and therefore expensive!) I want to put some local test subjects in. I did find a triplefin and he looks to be doing ok (although Im not sure ive managed to get him to eat) but I hear fish are fare more resilient to copper than snails/shrimp. Are most things I find in a rockpool ok to test? I saw a lot of little things zipping back and forth - are these mysis shrimp or some kind of pod? Can they go in ok? Cats eye snails or starfish?

They do look pretty cool, I'd love to have something like that at my desk. But man, a 2 gallon reef tank? You'd only need to sneeze on it to throw the water chemistry out

I'm in the process of setting up my first marine tank and as my current T8 bulbs are old I went to a local lighting shop to see if they had suitable high K bulbs. I got one rated at about 10k and an 'actinic', which they said is usally talked about in terms of wavelength ie nm than kelvin rating. The actinic light is almost more violet than blue. I was going to post a pic of it, but for some reason the photo does make it come across far more blue than in person. Is this 'normal'? Are actinic lights for aquarium usage different from general usage lights, for places like dark rooms? Will this be good for coral growth and showing off the tank inhabitants?

I'm fairly happy the way the plumbing worked out in the end, even if i did hit a few unforseen snags. The water level in the overflow area is quite low (as you can see in the pic) and the water has a long way to fall, but because its only working at around 1000L/hr over 35cm its a very thin layer of water and tends to 'stick to' and run down the glass overflow partition rather than just slopping over. The syphoning is happening from a bare bulkhead on the bottom and the standpipe is only a safety. I thought using the gate valve to regulate the flow out of the tank to match the flow going back in would be a real PITA. It's not at all. It seems to reach it's own equilibrium. I think its because closing the gate valve restricts the water flow (obviously), raising the water height in the overflow, which in term increases the water head, increasing the flow velocity. ie smaller diameter water flowing faster = same flow rate as larger stream of water at slower velocity. I'll have to run a few experiments. Funny really, because fluid dynamics was one of the reasons I didn't want to continue on with civil engineering Most of the noise actually seems to be from the power head, it makes quite the hum. Also the protein skimmer is not that quiet. Spoon, you'll have to come take a look

Thanks for the reply, Suphew. I'll be firing up the lights from here on. I replaced the bulbs on my tank today, as they were getting old. I have two 4ft t8s, one is a 10k the other is an actinic. There is also a 3ft single t8 on the tank with the stock tube in it - its a very crisp white light, so i'm imagining its in the daylight range. Will i need to replace this too, or can i keep the stock bulb? (its brand new) So basically im going through a mini cycle? Hopefully that means the bulk of the bacterial build up has been done. I'll recheck the water tomorrow and post the results. Here is how things are looking at this stage:

So after a few unforseen challenges regarding the plumbing that got me a little mad, I have the tank cycling and the protein skimmer working. Is it best for this stage to be done with the lights on or off? My first test results are a little confusing. pH - 8.0 Ammonia - 0.5 ppm Nitrite - 0 ppm Nitrate - 0 ppm Half of my coral rock was dry/dead and has been cycling in salt water in a rubber maid for almost a month. The other half is 'live' rock that was from someone elses tank but sitting in a black bin with a heater for a few weeks before I got it. Four days ago I filled up the tank with fresh water, added salt, waited a couple of hours and added my rock. Am I at the start or the end of the cylcing process? If i was at the end, wouldnt i expect to see some nitrate? or is that not the case because I cycled in different water from the tank ie 100% water change? :roll:

Time for my next seemingly random question The irrigation place i got my sump plumbing on recommended i get a big metal gate valve as it will allow best water flow control. But it looks like its made of brass to me... and that will rust up pretty bad in salt water in the long term won't it?

Not that i have any idea how to 'tune' a protein skimmer! :-?

After a couple of fresh water tests, im about to fill the tank for real. The coral rock I ahve has been cycling )or should i say cooking?) in a container of NSW in the garage for the last few weeks. When I've got the tank filled with salt water and add my rock, do I turn on the skimmer at this point? Or do i leave it off while cycling?

25% weekly sounds like a good water change to me, but LA indicated in his first reply that you may need to do that twice a week. Of course it depends on stocking levels and feeding etc

I'm currently fresh water testing my tank ie haven't done any water changes yet. My water change regimen will depend on whether I can spring for a protein skimmer or not, as this will help me cut down on them. I have a 240L + sump tank, so 20% for me is a heckuva lot worse than it is for you. I don't mean to discourage you from the NSW water change thing, just keep in mind you may find it to be a pain in future