Jeroen

Reef, Take some water of the skimmer and see if the Calcium is much higher then that of the aquarium itself. (can do the same for carbonate). Cheers, Jeroen

I bought this unit and a TDS meter. I am very happy with the purchase and don't think any retailer here in can beat that price. http://cgi.ebay.com/Aquarium-RO-2-DI-12 ... dZViewItem Jeroen.

I bought a 6-stage RO/DI unit with extra set of filters and TDS meter of e-bay from the states. All up for the great proce of NZ$ 360 including shipping what was about half the cost. 8) Makes you wonder why they are so expensive here in NZ.

Make sure that your test kit is right. I had an old test kit and thought that my nitrates were fine (5 ppm) untill I received a new kit which said that the nitrates were 10 times higher (50 ppm). My tank is still young (6 months) and find it hard to keep the nitrates low. Jeroen.

Hi, Just wondering if the meters tell you at what wavelength they are calibrated. Do they measure the intensity of light at 6500 Kelvin (or maybe even lower) or 14000 Kelvin. Can you adjust this? That would be interesting then you can check which part of the light spectrum fades quicker whne the light ages. Jeroen.

Reef, Would you know what light frequency the Lux meter measures? Do you see a difference when reading same strenght ligths at 6500K or 20000K.

Has anybody had a play with the simulator I posted? I was waiting for some comments. Again this only looks at skimming but if we increase the tank size in the model the water quality deteriates (or better said it takes much longer to remove all DOC). It takes more effort to get the all the DOC to the skimmer. Still take into acount what this mean in practise. The model show how long it takes for a skimmer to remove DOC. Like when you add fish food. Only the model assumes that all DOC is evenly distributed at the start what clearly is not the case. Still without the model I would not have thought about this point.

Amazing discussion ! Wonder if everybody talks about the same subject. So why not join in 8) and before people ask... I am an engineer too Even worse I am an engineer in applied physics. Although said that I always like the applied bit. There is nothing more valuable then field data. Back to the story. As I see it we have here several subjects. 1) The influence of a skimmer on dissolved organic compounds (DOC) in the system, 2) The production of DOC in the aquarium and how much a refugium contributes to this, 3) The effect of the system volume on DOC (longterm). It sounds like Layton is only talking about how a skimmer affects the DOC. On this I slightly disagree with him. The output of a skimmer depends on a lot of variables of which the particle size of the DOC is very important and this will vary over a very wide range in the aquarium. You will find that with equipment like skimmers that as long as you stay within the operating range of the skimmer the output hardly change when changing the concentration on the inlet (I have never seen a linear relation here in the field). To gain understanding of system models are very useful but only if you also understand the shortcomings of the model used. I have often discussion with process engineers about what the model predicts and what we find in the field. I have noticed that there are a lot of people that prefer to belief the models instead of the data from the field (To me these are the engineers that don't use the word applied). I found a very interesting model for skimming on the web (http://www.reefs.org/library/talklog/d_ ... 12499.html). It is does not state that this is the absolute model but looks at the influence of certain parameters on the system and states several of its limitations. I think it will entertain some us. The second point is more interesting and important to the subject. Unfortunately this is not an engineers subject and we have to rely on Feelers here . I really enjoy his input. It helps me to understand the system much better. I am still very new to the aquarium hobby and this part is not my strongest point. If I understand it well we like the refugium to be a good filter to remove ammonia /nitrite / nitrate but are worried about the extra bio-load it might give (organics). To me this sound like that there is an optimal filter size and if you have too much filter area (rock / sand) you start to pollute your system. Is this true Feelers? The last point is the influence of water volume on longterm DOC levels keeping everything else the same. There is no change in production of DOC or removal of DOC therefore the water volume will not influence the DOC level in the system. If the skimmer is the only part that removes DOC then whatever the tank volume the DOC will settle at the skimmers output of DOC. I just wish understanding all in the aquarium was as simple as engineering. Jeroen

Very interesting post. Feelers, I like your explanation on a sand bed. Reminds of the tread posted a month agon on the breeding station in the middle of the states that didn't use skimmers but very thick sand beds and just topped the sand up each year. Makes sense now. Loved the tanks on that post.

Impressed to see that they have the 14000K model too. Didn't know you them for growing herbs too? What kind of reflector would you use for these lights? Wish they had a shop here in New Plymouth :-? .

Great looking tank! . Do you like the overflow system?

The good thing is these are 1400K so suitable for a marine tank. I can't read the brand on the picture to see where else we can get them from. Still Aus$ 79 for a 400W compatible light and no ballast needed. Just wonder how long the last.

Has anyone experience with these lights or know if they are available in New Zealand. Could be an answer to our power bills. http://www.reefonline.com.au/shop/produ ... cts_id=214

Great story thanks :bounce: Always wondered how they would breed fish without skimming or filtering the planktonic stage out. Good to see that this is possible with such healthy looking tanks. Are that 400W or 1000W metal halides. Must be a nice powerbill.

Interesting question. As a newby to keeping fish I found it very difficult to figure out what to give them when and how much. Now a few months later I do something , the fish seem to like it a nd the nitrates have only slightly increased :-? but do think I have to cut the feeding back. I feed them flakes in the morning but miss some days out there the fish are almost still asleep when I go to work. In the evening I give them some frozen conccotion of mussels / king prawns / shrimps and what ever was on special and at the moment some frozen brine shrimp (had visited Hamilton). I got some freeze dried seaweed from an Aian shop what i give the 2 tangs some of about 3 times a week and about every other day I put a spirilina tablet in the aquarium where the fisg go completely crazy about. That means all but the one I bought the stuff for....my lawnmower blenny. He ignores all food and just eat algy of the tank. Does a great job but I do wonder if I have to help him abit to remove the algy there he is really fat. Back to the question of over feeding. My blue regal tang is clearly the boss and goes mental when you put food in the tank. Clearly afraid some other fish might get something too. He looks healty (not sure what a tang looks like when he is really fat). But I do know that he is the biggest polluter of the tank with his amount of fish pooh. So maybe when we feed our fish we should give them each there individual plates . At least then we know they all got some without the bullies getting to fat or pollute the tank too much.

Just wondering. Would adding cleaner shrimp be a good solution to treat whitespot?

Great looking tank! Love it! :bounce: :bounce:

Great Reef! . Missed your pictures. Beutifull tank.

Sorry, about your shrimp. A few weeks ago I got 2 yellow banded shrimps of which I hoped they were a pair but clairly not. Not good to lose something so soon. Surpised to hear that you can't have then for shrt moments in the air. My aquarium has an overflow with a lid on it with 2 narrow gaps for the water to flow. It seems that the yellow banded shrimp is a real night shrimp and hides with the first sign of light so I keep checking every morning if he is still there. Twice he wasn't and I looked al over the aquarium to finally find him, by pure luck being, being stuck in the overflow (tail sticking out in the air). Pulled him by the tail out of the overflow back in the tank. Hope he finally has learned his lesson. But no harm to the shrimp at all. Jeroen.

Sorry to hear . I have a lawnmower blanny since a few weeks and they are absolutely great. Real caracters. He is eating algy all the time trying very hard to keep the tank clean. Just wonder if they can overeat there he looks very fat. Jeroen

Must have cold nights in inglewood. Try covering your sump up as much as you can and insulate the box as good as you can. Wouldn't be surpised if it is all condensation. If you want to collect more salt water I will have the bilge pump in the back of the car at work (last unit of professional centre at Nobs Line). Cheers, Jeroen

I keep telling them at home that my aquarium is too small. Great pitcures. Thanks.

I want to go on a trip too!! :bounce: :bounce: :bounce:

Hi, I use them. Can get them free from work. Just have to rince them thoroughly but so far works really good. I use 2 x 200L drums to collect the water and the 100L bulky to store it. Just got myself a 2000 gallon/hr bilge pump to fill the drums. looking forward to try it (will be soon there the bulky is empty).

Thanks for all the advice, Tank is still very young (2 months) but has lots of life rock. Water parameters are very good. I can't detect amonia, nitrite or phosfate and nitrate is around 10 ppm. Calcium is around 400 ppm and SG is 1.024 and pH is rund 8.3. I use NSW and have so far not seen any changes in the parameters. I do about a 15% water change every 7 to 14 days. It looks like I might have had too much flow around them. I have re-directed my powerhead and they are calmer now. Haven't change the lighting yet and will see how it goes. It has not got any worse and maybe a bit better. Need more time to see. Will post some pictures tomorrow. Jeroen.