Water changes

[Mike L]

  This past fall I got back into the hobby after being out for 9+ years. I always kept/bred African cichlids. Started with Malawian for many years eventually settled on Tanganyikan as they became more common. I always did water changes in the 40-50% range weekly with the Malawian's and took that regiment to the tangs. They bred and some of the easier species lived for many years but I did have more trouble with the tangs dying off. Something I never had with the Malawians Was it the water changes or just that they are more difficult to care for.

Since my return to the hobby I am keeping and breeding Tangs again. I have heard so much variation on the amount of water to change in a tanganyikin tank. Just google and see. As low as 10% all the way up to 80% and was wondering what others do.
I currently change 25-30% percent weekly in my show and breeder tanks. I add  Seachem tang buffer, cichlid salt, and prime plus I make sure the water going in is within a degree of the tank water. All the fish appear fine, and my  Neolamprologus multi's even bred for me but I always wonder if I can do better. I'm I wasting my time with the Seachem salts and buffer. Should I be doing more or less with water changes/frequency.

I ask because I recently sold all the multi's and am now trying to breed yellow Calvus and I'm in the planning stages for a Neolamprologus cylindricus breeding tank.  These are more difficult to breed then the multi's and I want to ensure the best possible success.

Mike

[ajm1961]

I think cichlids in general are fairly hardy. However, some may be more susceptible to large swings in pH levels. I'm convinced that if you measured the pH before and after the water change, and it showed to have a significant variation, then you can expect the fish to feel that stress.

I found that peacocks were more susceptible to these changes than my mbuna. That's just my experience. With Tangs, if you're keeping the pH at higher levels, the parameter variation may be even more of an issue.
I'm not an expert, but in my opinion the essence is to try to keep the water parameters from changing too much in a short period of time.

For breeding, cooler water is definitely an inducing factor. Just ask Bruce (Bitterman) - his Frontosas will breed after water changes...

[Mike L]

  So what your saying is the % shouldn't matter.How much and how often do you change. I test before and after. I'm locked on 8.6 ph, gh kh at 300 +ppm. Also your suggesting that the temp does not matter at least putting in water say 2-3 degrees cooler would be fine and even beneficial for inducing breeding. I'm assuming by your comment that Bruce introduces cooler water in his changes and that the fluctuation of temp is a trigger that appears to induce breeding. I was always led to believe it was just the fresh oxygenated water.
Maybe bitterman can clarify 

[Shawn84]

Im no cichlid expert but from a breeding point of view. Doing a water change with a cooler water does or can play a role in trigger a fish to breed. Due to the cooler temp fish think its rainny season and will spawn. Then again the food you feed you fish also play a key in getting them to breed. On the water change you really got to find which % is best for  your fish. If you worried then do a drip system water change. Meaning you take the water out but when you refill the tank it take a long time. 

For example: it take me about an hour or so to refill my shrimp tank as they are really sensitive and csnt handle big changes. I do a out 15-20% ever 2 week.

[Stussi613]

Cooler water on changes always worked for me with Discus and Malawi Mbuna.  My yellow labs would go nuts breeding within 10 minutes of a water change.  I don't think percentage is critical, but I think 25% plus is probably needed to change the overall water temp.

[exv152]

If you're getting good results with 25%, I would stick with that. If you do 5-10% daily changes, over a shorter period, you'd get more clean water in there, and cause less water chemistry issues. This is a very effective way to reduce nitrates and not cause too much stress on the fish.

[fischkopp]

The amount of water changed does matter. If you say change 20% of water, you will have 80% of waste water in your tank remaining. Within the time till the next water change, more waste will accumulate, and if you remove only 20% of it the next time there will likely be more waste in the water than the previous time. Obviously, this all depends on many factors like how much waste is being generated, or how often the water changes happen, are there plants, etc. but you get the idea: with smaller water changes there will be be a relatively high build-up of waste in the water. You can plot all that in spreadsheet if you like, it's all simple math. If you do that you can see that weekly 10% water changes have almost no effect. For frequent/daily water changes 50% is a good amount, there is little value in doing more. And for weekly water changes 75% seems to be a good number that I try to follow (often do even more). There will still be waste accumulation, but the total waste in the water when the next change is due is going to be much lower.

In terms of waste, I heard from a fellow tang keeper (me don't keep africans) that nitrate should be a low as possible, like zeroish. To achieve that with water changes alone would keep you pretty busy. Another way is to remove nitrates via aerobic filtration. Fluidized sand beds work great for that and can strip a lot of nitrate. You still need to do water changes though to remove all the other waste products.

[Al]

if your water hardness is 300 and alkalinity at around the same your parameters are pretty good. at 300 you have HARD water and at 300 for alkalinity the buffering quality of your water is very good - buffering meaning the waters ability to prevent pH swings over time I don't know that I would be using additives with that water - I'd leave the chemistry alone As to water changes, tangs like stable water and are a little more touchy with water changes - some advocate 25- 30% weekly with some even doing it every 2 weeks. I have been a LT tang keeper and have always been successful with weekly 25-33% changes. Check your nitrate readings in your tank pre and post WC and you'll get a clearer picture, IF you use a good test - although high nitrates can be from a number of sources - fish waste, too much food be given, etc. Vacuum your substrate regularly with the WC and you'll be good to go but with your experience you probably know that. Good to see  a tang diehard, great fish and behaviours.
Good luck