growth rate related to tds

[springer]

When u are raising fry do they mature faster in a higher tds then a lower. and what would be a good number for the tds in raising fry.

[RogueDiscus]

I think it's generally accepted that fry need some of the minerals in their water. I forget who, but one of our knowledgeable members suggested that up to 180 ppm was beneficial. More than that does no harm, just doesn't help any.

[ericatdallas]

I forgot who but one of the members used to use RO discharge water from well... I have a tank with 800TDS for neocaridina and they do fine and that's supposed to be too high.

[DJW]

I forgot who but one of the members used to use RO discharge water from well... I have a tank with 800TDS for neocaridina and they do fine and that's supposed to be too high.

I think that was John Nicholson who used ro waste water. It worked for him but I don't know what the TDS was.

[LizStreithorst]

I used to use RO waste to raise fry, too. I did it to save water rather than make the fry grow faster.

Personally I don't think that it matters when it comes to growth rate. I am of the belief that fish get the minerals they need from their food, not their water.

[Willie]

I'm with Liz. Discus evolved in the Amazon where the water contains no measurable TDS so dissolved solids are unlikely to have a significant effect on growth.

In fact, John Nicholson does raise fry in RO waste, but frugality plays a major role in that decision. John also changes 100% of the water in his grow out tanks daily and that's the reason why he raises such good fry. I would spend my effort on water changes versus playing with TDS.

Willie

[warblad79]

230-325 TDS...I can grow my Giant Flora 6"+ in one year with 100% or more daily WC.

[LizStreithorst]

You must have missed what I said. It doesn't matter what your TDS is. The fish get their minerals from their food. If you take good care of them and change a ton of water it will help them grow larger faster and have a better shape. Willie said pretty much the same thing.

[warblad79]

You must have missed what I said. It doesn't matter what your TDS is. The fish get their minerals from their food. If you take good care of them and change a ton of water it will help them grow larger faster and have a better shape. Willie said pretty much the same thing.

Sorry but I have to disagree on that, try raising a batch of fry below 100 TDS and will see what happen.

[LizStreithorst]

I have raised batches in straight RO. That's how I know.

[warblad79]

I have raised batches in straight RO. That's how I know.

Please show us

[LizStreithorst]

It was a long time ago. I no longer do it. The RO is too costly. You sound like you don't believe me.

[brewmaster15]

I am going to have throw in my lot with Bryan, Eric and the others that think that the mineral content of the water affects growth. In my experience it does. Anyone here that has soft water and tried to raise fry in it has come across problems like short gill plates, short dorsal fins,Floppy fins, curved gill plates etc. These members have fed excellent foods and did excellent water changes and when they add minerals to the water...The defects no longer happen. I know from my own experiments that adding calcium chloride to my water or filtering through crushed coral improves my fishes growth and development as I have little calcium here in my water . Even Jack Wattley I believe noted that Discus Grow better in harder water. There was a case a long few years ago where a certain Breeder in Canada imported a bunch of high end wilds with the goal of offering F1 stock commercially and bred them in a recirculating system but the fry were raised in soft acidic water and though fed well and receiving good water changes, they literally were deformed by the lack of minerals in the water and stocking densities. There was a really bad fallout when these hit the market. The fry had bad fins and short gills.There are parts of Canada where the water is just too soft to support a tank of fry being grown in it.


I also have to agree to a large degree with Willie and Liz here too though.. That yes Discus did evolve in soft acidic water., with very little dissolved minerals. And probably evolved to get most of their minerals from their food. The difference is we aren't raising our discus as they would be raised in the wild of the Amazon tributaries.. we are feeding them multiple times a day diets that they did not evolve with and in waters that are vastly different from the Amazon and vastly different from hobbyist to hobbyist. We push their growth in pursuit of size and fast growth, I think this is why we have different experiences here with raising fry. There are too many variables that differ.

But we know that there is also the biological fact that discus do in fact take up calcium, magnesium and other trace minerals through their gills. This has been shown in multiple fresh water fish . Its even been shown in some fish that calcium is taken up by the skin. Fish gills have evolved to transport not just gases but transport many things which is why we can use many medication in the water. Since the Gills can and do take up at least calcium and magnesium and these are involved heavily in growth, It makes sense that having them in the water could affect growth., at least to me it does.

al

[Willie]

I don't dispute that discus can take up minerals through their gills. Whether that makes a significant difference in their growth is a completely different question. How much can they absorb through their gills versus eating food? It's like buying calcium fortified milk. Really?

That wild discus do not have short gill plates, etc., demonstrates that low TDS water does not cause deformations. Like Liz, I had terrible water problems back in the day and raised discus and angelfish on pure R/O for 5 years. (The water main in front of my house was replaced and whatever they were adding to seal the new main was killing my fish.) During that time, I raised plenty of big discus, had them spawn, and sold a lot of fry. (I'm back on tap water now and am sitting on that fantastic Merlin R/O system that they sell for $800 now.)

I don't see a big difference between soft or hard water and believe products like R/O Right reflect marketing hype. If anyone has evidence that hard water make better babies, I'm more than willing to listen. Especially the company that markets R/O Right. By the way, if you taste R/O Right, you'll know it's mostly sodium chloride. Otherwise, it's just opinion.

Willie

[brewmaster15]

Sorry Willie, I don't think you are taking all the facts into account here. .. I know from all your posts that you believe in extremely large water changes, and that you do these religiously. If you do that religiously with fry and RO water that may very well be akin to the water of the amazon as RO still has some traces in it, I know though from experience that if you slack on that water change system using pure Ro water your fry will suffer in growth. In harder water, even mildly harder water you have more leeway..One of the reasons for water changes is to replace minerals in the water.

A person doing 100% water changes daily with Ro water and one raising fry in RO water without that kind of Turn over will see growth differences even if they feed the exact same same food. Those differences aren't attributed to the bio-organics build up in the short term or bacteria, they are from mineral and traces being exhausted.

How many hobbyists out there mix back tap water 70-30, or 80-20, or even 90-10 with their RO? Why are they doing that ? to save 10-, 20, 30% RO? Its because they Grow better when they do.

I'm not saying that your experience with 100% water changes and Fry aren't relevant and don't work, but they don't discount that Fry grow better in harder water....just that you have raised good fry in RO water. They aren't mutually exclusive, but theres no doubt in my mind and in my water that fry grow better in harder water..

This is an interesting read, and the stories that came before. It illustrates what happens when you raise large number of fry in water thats too soft.

http://forum.simplydiscus.com/showth...ht=dale+jordan

al