Warren

Hi Midas, To date the cheapest option I've found to make med-large tanks is fibreglass over ply. I have a tank the size you mentioned 8'x3'x2' and its made from mainly 10mm glass. The bottom is toughened 10mm and the back is 15mm blue glass. The bottom piece is one of the old BNZ doors from Rotorua. The Back blue glass came from a church in Taupo. The rest was just found as second hand. The 10mm glass front has a safety margin of 2.0. Its a lot less than it should be but it seems to be ok. The tank is also 15 years old! Making the same tank using 12mm glass would give a safety margin of 3.0 Acrylic tanks do cost more. The panels also bend a lot. The edges have to be very accurately cut and be perfectly square. The glue has to be as thin as possible. I've talked a lot to Classique Plastics here in Napier about acrylic tanks, - they are difficult to build (large tanks) and require jigs to hold everything in place while the glue cures. I purchased one of their prototype tanks a couple of years ago. It is 900mm Diameter and 1000mm tall. It was designed to be a reef pinnacle tank. I'm currently using it for freshwater but plan to change it over to a coldwater marine tank. For my new big tank I decided to use glass for the front window and fibreglass over ply everywhere else. Because of the size and the number of earthquakes we get, I decided to use a welded metal frame also. The main reason was cost. I picked up 12 sheets of 19mm ply for free. I got most of the steel for the frame for virtually nothing. So far the only real cost was the front glass. This is 2900mm x 950mm and 19mm thick. I got lucky as there was an offcut from a big job in Auckland that was just about this size. It got trimmed up a bit and sent down to me for $1000.00 inc GST and freight. It was a good deal as the cheapest quote for cutting a piece specially was $1685.00 plus GST and freight. Was I glad this 'offcut' just happened to become available! It weighs in at 125kg. This sized panel only has a safety margin of 2.2, but it is a risk I'm willing to take. To get the proper safety margin of 3.8 it needed to be 25mm laminated glass (outside my budget). I've got a friend who can fibreglass and gelcoat the whole tank for $500. It should be possible to make an all-glass tanks using 10mm for under $1000 (including about $150 for the silicone). The glass should cost about $850.00 You will need to get lots of extra bracing pieces cut also. I normally double but every join on a tank this size. This give you a 20mm wide glue connection instead of only 10mm. It allows a lot more safety margin with the gluing. Use the Fosroc RTV silicone, not the Dow Corning. I've never had good long term success with the Dow Corning brand. Every tank I've ever used this stuff on has fallen apart. The Fosroc brand gets a 100% good tank rating to date. I have not tried Bostik yet. If you want a second hand tank, ring Rudi on 025 210 0297. He may still have some big tanks left to sell.

Have you considered second hand? If you choose carefully you can get some really good deals. Even though I can't imagine why, some people suddenly just give up on their fish hobby. If this happens they usually do not care how much they can get for their gear, they just want to free up the space it takes up. I've seen some good sized tanks on really nice stands in the 250-400L range go for between $250-500. They usually come with heaters and filters too. You'll have to be prepared to replace the accessories in fairly short order however just in case they stop working. Its like buying a second hand car, be prepared for a big bill not long after you get it. Over the years I've bought several second hand tanks. Usually a quick sand and coat of paint or varnish on the stand is all it takes to revive it to new condition. Keep an eye on your local Trade and Exchange (or equivalent) as really good deals pop up regularly.

Discus don't mind very gentle water flow. If the return water creates a strong current, that will be ok as long as other areas of the tank have a gentle flow. If you put Tetras in the tank they will like the water flow. They will probably spend hours playing in it. Discus also like lots of plants. If they have good hiding places in the tank they feel secure. They know they have a retreat and usually spend more time out front. My tank is very densly planted. You cannot see the back through the plants in most places. The discus know they can hide and sometimes do. If they are hiding you often cannot see any of them at all! Most of the time they are out in the front of the tank looking very happy and relaxed.

Hi Karen, I'd do 30-50% once a week if you can manage it. The fish will like it. I have used Geo-Liquid. As far as I can tell it is mainly a floculant. What floculants do is bind particles into larger groups called flocs. The filter can more easily and quickly remove the larger partilces. It works well to clear cloudy water, although it initially makes it really cloudy. I beleive it claims some other magic qualities as well. It probably adds some trace elements or other additives that may make the environment for the fish temporarily better. It seems pretty expensive for what it does. A small bottle of aqua-clear does the same job of clearing the water.

I've only ever seen bubbles on my amazonicus and bleheri sword plants, but not that many. The crypts don't ever seem to do it, probably because they grow so slow. I get 1 new full sized leaf every 2 days on most of my sword plants. On the osirus it starts off deep red and gets about 5 inches long on day 1 and continues to 10 inches turning green/red on day 2. The amazonicus starts off red/green and ends up green with some bubbles on the top half of the leaves. Cobomba piauhyensis grows about 5 inches a day and gets heaps of bubbles on it. So does Bacopa caroliniana and Rotala macrandra (as well as being bright red). These two only grow about 1 inch a day. Sometimes there are a few bubbles on the Glossostigma and tenelus. Your light intensity is probably too low to get much. With the type of plants you have, more light may promote algae. If all is growing well with little or no algae, I wouldn't worry if there are no bubbles. Many of my plants do not bubble either and they grow very quickly. I'm using 8 x 5 foot 58 Watt Colour96 Daylight tubes. They are 6500K white light with very high natural colour rendering. Its not a lot of watts, about 1.54 per gallon, but the tubes have a very high lumen output compared to many others (about double). All that matters is it works.

Bruce's setup was really good. I bought 2 of his fish at the club auction when he decided to change his tank style. They are great fish, strong colours and big - I've still got them. Don't let me put you off keeping them. They can look really good in a setup like Bruces, all I'm saying is if you want to guarantee results its best to do it the way that is known to work.

Hi Karen, Discus like very clean water and lots of water changes. The better you make their environment, the more colourful they will be. Many top breeder do 90% water changes twice a day! (Too much work if you ask me). Undergravel is fine, but you won't get the best success growing plants. You should also seriously consider getting and external canister filter to keep the water quality at a maximum. I'd wait at least 3 more weeks before getting any discus. Certainly get a few bottom dwellers to kick start things. They will also come in valuable later. Discus are voratious eaters of meaty type foods. They often tend to waste bits of food. Bottom dwellers are good to clean up. This is also why a good external canister filter is important. An undergravel just will not keep up with the loading. Whether you get a canister filter or not, I'd allow 3 weeks minimum to let the biological cycle complete before adding fish. If you do get a canister filter, start the 3 weeks from when you connect it in. Discus are expensive at the best of times. Do not rush the cycling of a tank. Dead discus will not only be costly, but dissapointing as well. If you add a biological starter culture it often kick starts things and can reduce the cycle time by a week, sometimes two. I just use dirt from the garden as it contains the same bacteria. It makes the water a bit cloudy for a day, but it clears. Discus are amazingly hardy. They are just a bit picky. To be at their very best they need the best of conditions. They will survive ok in less than optimal conditions, but you may be dissapointed if the clours do not show well. I've purchased or rescued a few discus from people who put them into community tanks. Sometimes thay are fine in community tanks, but mostly they turn grey and lose most of their colour. Once put back into a discus only tank they colour up again with about 3 months.

I only buy comercial units. I get them at trade with a small discount through my work. I have a 5000L/hour sumps pump (Cost $225.00 4 years ago) and a couple of 22000L/hour Sump Pumps ($305.00ea 2 years ago). The 22000 L/hour pumps are not rated for 100% duty, but have been running 24/7 for the last 2 years. They are Grunfos which seem to amoung the best you can get in NZ. You get a lot more pump for your $$ when you buy a comercial one but the problem is they are usually much bigger (>5000L/hour) and use more power (>100 Watts). This certainly adds up. A pump if running at full capacity 24/7 will usually use between 5 and 8 times its purchase price every year in power. This is not so for smaller pumps which use a lot less and larger pumps use a lot more.

Any submersable aquarium or pond pump will usually do. The cheaper ones are usually noisier and don't last very long, but this is not so important as this pump will only get intermittent use and will probably live outside. You will probably need a 600-800L per hour pump with a zero head. Just check the side of the box the pump is in, or the info leaflet inside for the pump curves. Pick the flow rate you want and match it to the head. It will show which pump in the range to choose if its not the one you picked up.

They have a really good range. Heaps of display tanks. They're the only place I've ever seen more than 1 redline batfish (the black one with the thin red line round the perimeter of its fins), - they had about a dozen! I wanted to take one home!!!!!!!!!!!!!! I did not have much time in Melborne, - finished the job I was doing at 9:00am and had to fly out at 6:00pm. I only got to visit 6 aquarium shops and 2 HIFI shop, but this was one of those shops you always remember. Next time in Melborne, worth a look.

I use ex-soap tanks from the local tanery. I've washed them out very thoroughly and joined 2 together. I use 2 more as coldwater ponds.

Hi Arly, Have you visited Redwood Aquatics. They are pretty good. I've found Bob Ward (the owner) to be pretty good. I have no experience with the other staff, but if the general philosophy Bob has is present in his staff they will be good too. Their range of marines isn't too bad either.

Hello Karen and Welcome, Your tank is approx 150L. You are lucky, as Australia does not have too bad a range of Discus. NZ is pretty poor, - it seems to get all the reject fish. Even the ones they call 'Good Quality' are not very good when stacked up against Australia (or other parts of the world). I believe Coburg Aquariums could be in your area, although Vic is a pretty big place (although anywhere that not NZ is pretty big). Its just the best one I found in Melbourne anyway. If you don't know of them, here are their details: Coburg Aquariums 232-236 Bell St, Coburg Melbourne Ph 03 9354 5843 In a tank of 150L I'd put a maximum of 3-4 discus. They really need about 100L each as adults to be totally happy, but people seem to get away with a lot less. The problem is discus have a bit of a pecking order. Its usually best to keep them in a large group 8-12 is good. This requires a medium sized tank however of about 500-800L. If too few discus are kept together, one may get bullied too much. This can cause undue stress so the fish does not eat and slowly wastes away. Sometimes you get lucky however. If you can plant the tank quite densely it will help a lot with any bullying that may happen. I will be setting up a new tank soon with about 35 discus in it. I'm looking for a couple of good breeding pairs at the moment as I can't afford to buy 35 imported fish. I'll have settle for a couple of pairs of the ones we get imported and try to breed lots. The best money you can spend on discus is on books. Get a couple of good ones and you'll find all you need to know. A couple of good ones are 'Handbook of Discus - Jack Wattley' ISBN 0-86622-037-2 and 'Discus for the Perfectionist - Jack Wattley' ISBN 0-86622-168-9. I hope this helps a little.

Only the 20L of salt mix is gravity fed. The 600L comes from a 2000L outside storage tank and is pumped and preheated by a phase controlled 8kW heater element. This regulates the ouput temperature to 26'C ±0.5'C.

Hi Kevin, What do you mean by pearling? I've not used a DIY mix, only gas cylinders so I know nothing about them. I'd expect however that you could use a bigger bottle with a larger mix if you want more CO2. If by pearling you mean oxygen bubbles forming on the leaves of the plants, you will also have to have the correct lighting. Just adding more CO2 will not create oxygen bubbles if the lighting is too weak, - the two must be balanced. A little experimenting will be required also. Depending on the type of lights (colour spectrum) you may need more intense lighting (Watts per Litre) if the colour spectrum is not ideal.

There is a brand of heater I've seen advertised in TFH that uses triacs. I don't know if it is available in NZ. Virgil is right about the triacs. We use a slight variation of the triac at my work and they are ultra reliable. It is a good way to majorly increase the reliable life of a heater. The only big problem is making sure you get the same water seal once the heater is reassembled. You don't want to mess with water and 230V, -oooh nasty. If anyone is interested in doing the mods, I can supply suitable triacs, - I'll even sell them to you at cost!

You asked for it... I use RO water exclusively in all may tanks. The fishroom has a continuous trickle of RO water entering the central filter sump. The excess overflows down the drain. Every 30 minutes, a dosing pump adds the following: 1. Sodium Bicarbonate 2. Calcium Chloride 3. Magnesium Sulphate 4. Potassium Sulphate 5. Sulphuric Acid The 4 salts and the acid are premixed with water and stored in 25L tanks. The dosing pump adds a few drops of each to the sump every 30 minutes. The acid is added at the opposite end of the sump. This allows it to mix in ionically without reacting with the salts. This keeps a stable pH of 6.8 a KH of 30ppm and a GH of 60ppm. I get away with such soft water due to the continuous water change / dosing process. I keep mainly South American Cichlids and Tetras and they seem to like the soft water. They certainly spawn lots. The inside display tanks, I add the same relative level of salts during a water change. The daily fertiliser dose contains the correct balance of salts to ensure stable pH of 6.8 all the time. It may fluctuate a little on a daily basis between doses, but it will not be more than 0.2ppm. The fish don't seem to care. Water changes are 50% one per week. I have levels marked on the tanks so I know how much to take out. I then know how much salt to add during the refilling process. Filling take about 1 hour (600L of water), and the salt mix is added from 3 containers using gravity feed. The hoses have a tap to adjust the flow so it take about 1 hour to add all the salt mix. The above salts represent the most dominant salts present in natural waterways of South America. I got the information about the natural waterways from a book called the Optimum Aquarium. Unfortunately this book is no longer in print. It was written by the Dupla guys, who actually went to South America and measured the water parameters of many of the streams and rivers. It is the best book I've ever seen for the serious fishkeeper. I no longer have the book (it was borrowed), but would like to buy it from anyone who has a copy they do not want any more. I think it is worth a bar of gold! Anyway, back to the salts. They are mixed to as closely represent the compounds found in nature. It seems to work, - the fish are very strong and happy. Water out for pH adjusters sold in Pet Shops. If they do not have the ingredients printed on the outside, they probably contain Phosphate based salts. These are very good a producing large quantities of algae. Look for products that do not contain any Phosphate. The best and cheapest KH buffer seems to be Sodium Bicarbonate or Baking Soda as it is more commonly known. Dupla sells a KH buffer for about $20 that treats about 250L of water and raises the KH by 15ppm. I suspect it is Sodium Bicarbonate or something very similar. $20 will buy about 8kg of Sodium Bicarbonate from your local pool shop. This will last most aquarists about 2-3 years. Likewise with the GH buffers, most are available in bulk (like 2-4kg's) from the pool shop or industrial chemical supplier for less than it costs to treat your tank once. I don't mean to upset the retailers, but there are limits to what people with more than 20 tanks can afford. I go through 4kg of sodium bicarbonate in a year and 2-3kg of the other salts in the same time. I could not afford to buy these quantities retail without shutting down some tanks. I suppose I should mention why I use RO water. Our lovely tap water has too much phosphate - about 8ppm too much. Everything else about it is pretty much perfect, - no chlorine, pH near 7.0 KH about 50ppm and GH about 90ppm, no Nitrate, Nitrite or Ammonia.

Cool, thanks Cees. I'm pretty good at getting carried away once I get started on something. I tend not to notice what originally set me off on the path...

Hi Benny, I got 96 in school C and 97 in UE. I've also done tertiary mechanics + physics. I've never done structural engineering however. It is not too difficult to grasp the basics if you have a reasonable understanding of physics and mechanics to start with. The maths isn't too hard. Its about the same as 6th form calculus. Most of it is common sense. If you have a big tank sitting on a stand and you push against and it moves at all, then it is going to break in a big earthquake. The rim that runs around most people tank is usually not strong enough. If you think you can rip it off if you grab it in your hands and really heave on it, then its not strong enough. Try to put things in perspective. If the tiny amount of force a person can exert on a stand can move it, this is nothing compared to what it will see in a decent earthquake. It does not cost much extra to build a stand to hold a tank in place properly. In most cases its only a couple of dollars of extra screws. I've seen Caryl's setup and it looks really strong. The only bit I'd be concerned about is the front strip across the bottom of the tank. It may not have enough screws in it to stop it breaking off in a 'Big One'. It should have at least 10 screws evenly distributed across its length. Each screw is good for approx 50kg, so 10 will give nearly 500kg of protection if the tank moves all at once and not one end first. If the tank is 350L it is probably at least 500kg all up in weight. The unit will support it no problem as it is built into the structure of the house. At the end of the day, you can only do so much. The idea is to do the best you practically can. There is always the chance of an earthquake that is so big that nothing will save the tank. All you really get by trying to earthquake proof your tanks is piece of mind. They will probably survive if you've taken the necessary precautions but there is no guarantee. The fingers crossed method seems to work pretty well for most of us.

There are 2 ways to protect against earthquake. For both, the first thing you need to find out is the maximum G-Force an earthquake in your area will subject the objects in your house to. This is a bit of a grey area, because all you can use for this information is the maximum measured force during the History of the area. This does not of course guarantee there won't be a bigger earthquake in the future. I my area, the largest recorded earth quake measured 7.2 The recommended G-Force for the area is 0.7 I have doubled this to be safe. This means an acceleration force of 1.4G's in any direction. Protection methods: 1. Flexible Stand: Allows the tank to move on its stand, ie allows the stand to flex. This method serves to reduce the forces on the tank. It works very well provided the extremities of the stands ability to flex are not reached. If they are the stand will break. I do not use this method as I do not yet know how to calculate the stand requirements. It also better suits smaller tanks. 2. Rigid Stand: The stand in this case is strong enough to support the tank rigidly. All the forces from the earthquake are transferred into the tank in this circumstance. The tank design must therefore be able to withstand 1.4 x the normal forces it would usually take. Glass is a quite magic substance as it can naturally take very short impulse loads up to approx 200%. No extra design is usually needed in the tank design to allow for earthquakes if the tank has been designed properly from the start (see my glass thickness article - from the FNZAS home-page). The stand must be strong enough to take the full weight of the tank + stand x 1.4 with the force coming from any direction. The tank will need a rim all the way round its perimeter to stop it sliding off the stand. The rim needs to be able to support 1.4 x the weight of the tank. The tank must be strapped down to the stand so it cannot jump off. You guessed it, the straps must be able to support 1.4x the weight of the tank. The stand must be able to support 1.4 x the weight of the tank + the weight of the stand. The stand will need to be bolted down to the floor to stop the whole lot (tank + stand) from jumping round. The floor needs to be able to support 1.4x the weight of the tank + stand. If it is a wooden floor, you may have to strengthen it by adding new piles. You will also need to check the lateral stability of your foundation to make sure it is rated to carry the extra side forces from the tank + stand. Two Examples: Warrens Current Tank #1: Tank is 2400 x 820 x 680mm and hold 1200kg of water (8 x 3.25 x 2.2 feet - 300Gal 2640lb water). The stand weighs 400kg (880lb). The total weight for the system is 2400kg (5280lb). The maximum force I have allowed for is 33600N (Newtons) or 3360kg (7392lb) of force in any direction. The ring foundation that supports my wooden floor is capable of withstanding the lateral load, but the floor isn't. I added 6 new piles under the floor directly under the tank set in a 600mm (2 foot) square concrete pad. Warrens New Tank: Tank is 3100 x 1000 x 1200mm and holds 2970kg of water. The stand is built as a steel plinth 200mm tall and forms the base of the tank. The total weight is approx 4500kg (9900lb). The design loading for this tank is 63000N or 6300kg. This is 6.3 tonnes, about 4 x that of the average family car! This tank will sit on the same floor as the previous tank. The floor will not support the weight and the ring foundation will not support the extra lateral force in an earthquake. This time I have to add a welded steel frame under the floor set in 8 x 600mm concrete pads. The frame will be diagonally braced to support 100% of the lateral load. This will decouple all the forces from an earthquake and transfer them directly into the ground. These measures may seem a little extreme to some people. I however value my fish and take the appropriate action to ensure their survival through a large earthquake. With some luck they will come through it better than me. Not everyone has tanks as large as these, but some people have larger ones. The biggest problem faced by most people is just not being sure what to do to protect their tank. The forces involved in an earthquake are often very hard to imagine. Unfortunately the calculations required to work out just what is required are very specialised. The people who know how to do it are highly qualified. Just the maths alone is beyond most of us. The only solution open to most is to get a structural engineer to go the calculations for us. The first time I ever made a big tank properly I used a structural engineer. It cost $400.00 for the analysis, but it saved me more than that in materials when I went to build it. In the process, I also learned from the structural engineers how to do the calculations. My maths is reasonably good so I was lucky to be able to understand it. However, this is because I've got an engineering background to start with. It may be beyond some people to understand and others just won't want to put in the effort to learn. For those people, they will have to pay someone to do the calcs for them. I hope this helps.

I am using standard packing grade prlywood. It is 19mm thick (3/4 inch) and I'm using 2 layers. This is covered by copstrand fibreglass and polyester resin. I am not using epoxy resin as it is not water proof. The top layer is gelcoat (black) used to seal the tank. The gelcoat is very hard and quite resistant to abrasions. My only concern is cracking the gelcoat if a rock ever falls over. It may be better to use the stuff Bill is mentioning. I've seen it before and it is available in NZ. It is used on Ponds and Pools to seal the concrete. It is not cheap however (probably at least $100 for a tank the size you propose) beacuase it a very speciallised paint. I'm using Gelcoat because a freind can bo it for me really cheap with a spray gun. Likewise, the chopstrand and polyester get sprayed on using a special machine. All you then have to do is roll it out and you're all done.

Hi All, Looks like I need to chase a few people. The payment received was from NZKA. It is the registration fee for 2 people but to date they have only registerred 1. Today I received a large payment from the Upper Hutt club. I have no registration forms for them!!! Who is coming from Upper Hutt. Please fill out the registration forms and send back pronto. Also, have not heard from Waikato, come on guys. Some of you seem to need rockets put under you! Money about 1 week before conference would be good (thats May 23rd if you can't work it out - just over a week from now!!!!!!!). That way we know where we stand for $$ and how much we're gonna need to screw you all in the raffles and auctions.

Thanks everyone. Looks like black it is. I was pretty much set on it anyway but it's always nice to have it confirmed by others.

I have P.Norths registrations for their delegates. Also 1 payment without a registration (???????!!!....) Caryl is right. It is my own fault. I neglected to put a return date thinking people would want to get their registration in quickly. How wrong I seem to have been. Its sad to see... Yes Caryl, I have yours, all processed. Just waiting for everyone elses now... and ...... .... .... and some more ..... Oh well, tired of waiting, I'm going to do something else.

Interesting background colour in Dana's tank. I am still trying to decide what colour to paint the inside of mine. I am thinking black to enhance the contrast to the plants but have heard it can make the fish less happy and colourful. I don't really like light blue because it seems to dominate the tank so much. With the quantity of plants however it is unlikely you'll see much of the blue. I am thinking , if the tank is very heavily planted (so you can't see much of the background colour) it may not matter so much if it is black. I want to get it right first time. Stripping down a tank this big to repaint is something I don't want to do. Comments on the colour I should use please...