Neocaridina failed molt, low KH?

[plecc83]

Hi all,

I have a small 50L yellow neocaridina tank, the tank is quite mature over a year old. But its only had the 6 shrimp and a rabbit snail in there for 3 months.

I think I have just had my first failed molt, I left the shrimp in the tank just in case it's still mid-molt but I'm fairly certain its died. it appears the shell split successfully and the tail is completely out but the front 1/2 is still attached.
I'm very inexperienced with keeping neo's, is this just something that happens every now and then? or is this an indication of a problem that needs sorting out? my KH appears to be vey low compared to my other tanks that contain slate and sand.

The tank doesn't contain any stone/rock or gravel/sand.
Décor - Malaysian bog wood and Catappa leaves
Substrate - Fluval Stratum (mixture of live plants)
Filter - Matten foam panel driven by powerhead to spray-bar.
W/C schedule - 10% weekly, filled very slowly (4 days since last w/c)
I don't use any shrimp minerals in my water changes just prime water conditioner.

Food - Snowflake & Fishscience Shrimp Sticks (both fed most days), Blanched vegies usually cucumber (once a week over 2 days)

Current stat's
Temp - 24.3 C
GH (ppm) - 180
KH (ppm) - 40 (My other tanks are typically very high KH-240)
pH - 7.0
Nitrite (NO2) - 0
Nitrate (NO3) - <10
Ammonia (NH3/NH4)- 0
TDS - 150-250
(my TDS meter only measures in increments of 100 ppm)

Any help's greatly appreciated, am I also running the tank a bit too hot?

 

[Sgooosh]

yea, i think your kh is a bit low...

 

[plecc83]

Thanks for the quick reply

I just checked out my tap water,
GH - 180
KH - 180
pH - 7.0
NO2 - 0.5
NO3 - 20

So the shrimp tanks setup is defiantly pulling down the KH.
I have been trying to reduce water changes as much as possible on this tank as most of the YouTube guys recommend for reducing stress molts.
I think this has also helped the KH get really low.

What do you think is the best method for bringing my KH back up?
1. More frequent or larger water changes.
2. Add crushed coral/coral sand or maybe egg shells.
(I also have some Calci Dust 100% calcium carbonate powder typically used as a food additive for reptiles)
3. Add a shrimp specific mineral additive to buffer KH.

 

[Sgooosh]

First do a big water change to get the nitrates out of water
Let them eat egg shells
Put crushed corals

i think you should move thren to another tank in the mean time with a breeder box

 

[seangee]

In my shrimp tank the GH is 100 and KH 50. Your temp is fine, I keep mine at 24 but in summer it often gets to 30.
I change 75-80% of the water weekly. Water changes cause a lot less stress than unstable parameters (like KH dropping over time). If you do a significant change every week it means the water in the tank will remain very similar to what is in your tap and stay stable. Neos are fine with a fairly wide range of parameters.
Keeping your tank close to your tap water is a good idea in case you ever need to do an emergency change due to accidental contamination.

Edit: The stress they refer to is changing water parameters - not changing water itself. The best way to avoid this is regular substantial changes.

 

[Lajos_Detari]

Firstly, I don't think you need to do anything with your KH.

Your GH and KH are high though Neocaridina shrimps can adapt to wide range of GH.
The recommended GH is between 6-8. And KH of 1-4.

Water Parameters Needed For Shrimp: Temperature, KH, pH & TDS

Neocaridina shrimp water parameters, like pH, should be correct as well as constant. Water parameres like pH and TDS for other species like red cherry shrimp should be stable as well.

theaquariumadviser.com

You shouldn't add more minerals or Calcium into your tank, else your GH will be worse.

My theory of failed molting:
I am suspecting that our tap water GH, TDS or the minerals content is different from the shrimps farms. These are the main cause of failed molting and white rings.
Many of my first batch of shrimps had the same problems even though my tap water GH is 5-6, and I changed only 15-20% of water at the beginning.

Water changes may not really affect the molting issue unless your tank water chemistry is too much different from your tap water.
As Sean mentioned above, I am also changing about 60-70% of my tank water once a week without any shrimps dying or having molting issues.

Your only hope is probably to feed them with enough Calcium supplements.
Your next generation of shrimps that are born in your tank won't have any molting issues as they are used to your tap water.
My current generation of shrimps don't have any molting issues and they are super hardy as they have get used to my tap water.

 

[Lajos_Detari]

Here are some shrimps food recommendation:
Mulberry and Kale leaves also have high Calcium.
They are also sold in pellets form.

White Pellet - Calcium Supplement (Shrimp)

Shop our Green Leaf Aquariums White Pellet - Calcium Supplement (Shrimp). Planted aquarium boutique since 2007 & 24/7 customer support, we ship fast!

greenleafaquariums.com

The BIG shrimp food test

www.practicalfishkeeping.co.uk

Shrimp Food – Page 2 – Green Chapter

Staple and supplementary food for upkeeping of ornamental shrimps such as cardina, neocaridina.

green-chapter-shop.myshopify.com

 

[Yohance1130]

there is a chance you can cause more stress then needed to your shrimp and possibly kill more of them by trying to chase parameters since it can stress them out even more. A KH of 40 ppm is fine for Neo's my aquarium full of cherry shrimp has not had any failed molts and my Gh is 8 degrees and my Kh is 5 degrees.

Neo's are very hardy and well adapt to most of your parameters, it would be better to feed calcium rich foods instead of trying to change your parameters. Some of the calcium rich foods you can feed your shrimp are foods like spinach, Hikari shrimp cuisine etc... Any veggies high in calcium are good, Most of the foods that are specialized for shrimp contain calcium and also many of the minerals needed for shrimp to thrive.

 

[plecc83]

Thanks everyone for the great feedback!

I did a 20% water change last night and another 20% this morning.
I do actually have a free cycled tank available at the moment, that has the high GH & KH that matches my current tap water readings, so relocating them is an option.

I was under the impression that the FishScience shrimp sticks that I've been feeding had all their requirements met, they claim "Contains optimal calcium and mineral levels for exoskeleton formation".
But I managed to pick up a pack of Hikari Crab Cuisine earlier, which claims "This uniquely balanced formulation offers necessary nutrients that promote proper shell development"
Both the above foods fail to mention how much calcium and/or minerals they contain, I was thinking that crabs typically have much thicker shells than shrimp and so, I was hoping the crab cuisine may contain greater levels of the required calcium and minerals. LOL, this seamed logical at the time but I'm now wondering if its not much better that the FS shrimp sticks.
They also had Hikari Shrimp Cuisine but it didn't mention anything on the packet regarding calcium or shell development.
I wasn't able to get any of the more specialist shrimp foods from my LFS, but I can order a pack of the white pellets if you think I would be better option than the FishScience / Hikari foods?

I have added a few pieces of egg shell as well. Is it ok to leave the shell as large pieces or should I have crushed it into a sand like texture?
So will shrimp and snails actually eat the egg shell?

Its great to hear that you are all able to do such large & frequent water changes on your shrimp tanks without issues, all of my previous shrimp related research had lead me to believe that large water changes would be a death sentence!

I'm quite confused about what I should do next,
Should I keep them in the current tank and continue to do 20% water changes every 12 hours to slowly adjust the tank to match my tap water, and then start doing much larger water changes during my weekly maintenance?
or should I acclimatise them to the other tank which is already much closer to my tap water stat's? (I'm fairly sure this tank has much higher calcium and minerals in the water column as snails tend to do really well in it)

Do you think the crab cuisine will be good enough? I will try and get some high calcium vegies to feed tomorrow.

Thanks again everyone.

 

[seangee]

A daily 20% change for a week followed by a 50% change should do the trick. Then just settle into your new routine. FWIW mine just get good quality fish food with the occasional treat of spinach or blanched green veg.

 

[plecc83]

Great! will do.
I was planning on getting some spinach, how do you feed spinach leaves?
Do you just blanch them and then pin them under a rock in the tank?

Thanks for the help.

 

[Lajos_Detari]

By the way, you only have 6 few shrimps in your 50 liter tank.
Your bio-load is super low.
Probably, you don't need to change so much water like us.

I have a 60 liter tank with 100-200 shrimps plus some Chili Rasboras and male Endlers.
So, my tank bio-load is high and I have to change more water each week.

For your case, probably 30% once a week is more than enough.(just my estimation).

Since the problem is caused by GH issue and probably not having enough Calcium and other minerals in their diet and water, my suggestions are:

A good reading to understand about GH:

Water Parameters: Everything about GH in Shrimp Tank - Shrimp and Snail Breeder

General Hardness (GH or Total Hardness) is an important water parameter to shrimp keeping and breeding. Unfortunately, Carbonate Hardness (KH) and General Hardness (GH) are commonly confused. General Hardness (GH) represents the overall concentration of salts (calcium, magnesium, iron, etc.) but...

aquariumbreeder.com

1)Provide more varieties of food especially high quality food(as Sean mentioned).
I have no idea about the Calcium content in the shrimps pellets.
For the snowflakes, I don't see any mentioned of Calcium at all.

Check the shrimp food contents and I guess the more expensive foods usually will have better quality ingredients.

2)Get some pellets that have high mineral and plants contents.

Here are some shrimp minerals:

Shrimp King Mineral - Dennerle (EN)

Mineral food for shrimp Food sticks for selective nutritional supplementation with the extra portion of minerals With 7% calcium and 10% montmorillonite Sinkable, water-stable food sticks made from 100% natural ingredients for specific mineral supplementation Supports molting and a strong shell

dennerle.com

Mulberry leaves in pellets form:

GlasGarten - Shrimp Snacks - Mulberry

Shrimp snacks are a tasty snack for your shrimp, crabs and snails. Because of the natural ingredients' own aroma, shrimp and Co. are immediately curious and the appetite is...

www.aquasabi.com

Hikari crab cuisine:

Crab Cuisine - Hikari Sales USA

A Scientific Diet For All Crustaceans Including Hermit Crabs, Lobsters, Crawfish And All Freshwater And Marine Scavengers Who Normally Have To Rely On Leftovers From Others!

www.hikariusa.com

Hikari shrimp cuisine:

Shrimp Cuisine™ - Hikari Sales USA

Shrimp Cuisine has been scientifically developed after considerable research into the nutritional requirements of delicate and higher end shrimp and utilizes a wide range of ingredients including vegetable matter that herbivorous shrimp prefer like seaweed and spirulina.

www.hikariusa.com

 

[Yohance1130]

Great! will do.
I was planning on getting some spinach, how do you feed spinach leaves?
Do you just blanch them and then pin them under a rock in the tank?

Thanks for the help.

To feed the spinach leaves.

Boil hot water, add the spinach leaves to the boiling water for 5 mins so that it becomes soft enough for the shrimp to eat. Take it out let it cool for 5 mins, then add it to your tank, I believe they still float after being boiled so you will most likely have to pin them with a rock or something.

 

[StevenF]

Yourtap water has a GH of 180ppm. That means you have have more than enough calcium and magnesium in the water. KH is a measure of carbonate levels. Shrimp don't care about KH as long as the PH is stable. shrimp will do fine in water with a KH of zero as long as GH is sufficient and PH is stable. I see no see any to increase calcium levels in the water. increasing the variety of foods you feed to your shrimp is good but it is not going to make any big difference in Calcium (Ca) and magnesium (Mg) levels

Sometimes molting failure is cause by low GH level or an imbalance in calcium and magnesium levels. Sometimes molting failures have nothing to do with GH, PH, and KH.

However in your case you tried reducing water changes. Doing that can creat a calcium / magnesium imbalance in the water. lack of water changes in a planted tank are can cause very low calcium levels and high magnesium levels. Its is also possible to have high calcium levels and low magnesium levels. Either way an imbalance in Ca and MG is bad and could cause a molting failure.

when you increased your water change amount and got the tap to tank water to match you reset the tanks nutrient imbalances tank to match your tap water. Which is the nutrient balance you tank had when you first set it up.

At this point i would simply continue the larger water changes once a week and monitor your tank and shrimp before making any more changes to your tank. I strongly suspect the larger water changes have fixed your problem.