Things I’ve learnt by killing my CRS

I have read almost every CRS guide that I could find on the internet. Some of them are heavily biased towards a particular brand and make things look so easy! Then why do people across the world complain about it being tough? Because it is! Here are a list of things I’ve learnt through my losses, things most of the guides do not say or emphasize.

Test Kits: (GH/KH, TDS, pH)
The single most important kit you need is the GH/KH test kit. Yes, I know GH can be guessed from the TDS, but first of all, when it comes to CRS, guessing does not bring any good, second of all, read first of all. CRS has a wide range of acceptibility for TDS (90-150, even 200) than it has for GH (4-6). Keeping a TDS of 120 does not ensure your water has the perfect GH for shrimps to molt properly. You should mineralize your RO water to have a GH between 4-6 not for a certain TDS. Then whatever the TDS the mixture reaches, thats the TDS you should aim for always. KH also plays an important role in keeping the water parameters stable, specially the pH. Internet says its okay to have KH 0 but in fact its not. Having a KH 0 means your water is prone to sudden pH swings. Having a KH value of 1-2 is equally important. You should also aim for a pH below 7.0 but this is not the end of the world, slightly above 7.0 is okay too as long as it always remains that way.

RO Water pH:
It is advisable to use RO water for CRS. Dont get fooled by the pH measurement of the bottled RO water. It will read way below 7 but if you keep it in an open place for an hour or two or preferably overnight, it will climb towards 7 or even above 7. Do not ever measure the pH of the water unless its been aged for a couple of hours to 24 hours depending on the water volume.

You should always aim for a soil that buffers the pH of the tank to less than 7. But if your water has a very high KH, the substrate can not help you. Amazonia II buffers the soil around pH 6.5, Africana to pH 6.0 and Malaya to Ph 5.5 approximately. Please note tha you must have a fat (at least 4cm) layer of substrate for the soil to be able to buffer properly.

Temperature:Do not even think of keeping CRS in temperatures above 26C. You will not have much success. The ideal temperature is between 21C and 23C but keeping a stable temperature without fluctuations is much more important than struggling to keep it low. That means, if you can manage to keep the temperature stable at 25C, that is the better option than trying to force it to 22C but fluctuating it between 21C and 26C.

Water Change:
When it comes to CRS, what do we say to frequent water changes? Not anymore! Frequent water changes cause more stress and does more harm than good. If there is one single thing CRS dont like, its “CHANGE”. If your Ammonia, Nitrite and Nitrate reads within the safe zone, dont change water. If you have a good filtration, you could go upto 6-8 weeks without water changes.

Also make sure your water is aged at least a week before releasing CRS into the tank. This means, do a 80-90% water change on week prior to introducing CRS. Check for water parameters one day before and make sure they are stable. This means, your tank water should read:

Ammonia/Nitrite: 0
Nitrate: 0-5
pH: 6.0 to 7.4
GH: 4-6
KH: 1-2
TDS 90 – 150

No planted tank:
It is impossible to balance the need of a proper planted tank and CRS at the same time. Pick one. Yes, your tank better have some plants for CRS, but those should be low demanding plants i.e moss, ferns etc, not resource hungry red plants or hairgrass. CO2 is also a big NO, in fact CRS prefer a O2 rich water.

I would avoid having any kind of stones at all, other than may be those mineral stones sold specifically for shrimps. Rocks and stones may cause the GH instability in the tank and also cause pH swings overnight. However, driftwoods are okay, in fact preferable. Its better to set a dedicated tank up for CRS using a fat layer of substrate, easy low tech plants like moss and ferns tied on branch wood and optionally mineral stones. No fancy rocks, no fancy plants!

Again, CRS do not like changes. Do not put your hand inside the tank, like ever. Use a long twizzers to do stuffs you’d use your hands for.

And now, some pictures of my CRS, which I’ve lost in the process of learning.

Crystal Red Shrimp

SS/K10 Crystal Red Shrimp

Golden Bee Shrimp

Golden Bee Shrimp


Iwagumi Bowl

My iBowl – 5g Iwagumi Bowl

The journey started when I got addicted to Iwagumis but my wife would not allow another tank in my home. Due to warm and dry weather conditions in Bangladesh, I had bad experiences with Hemianthus Cuba (HC) before, so I wanted to set this up inside an air-conditioned room! Luckily, a 5 gallons bowl did not count as a *tank* and I somehow magically convinced (read blackmailed) my wife to place it inside our bedroom. She even went as far as buying the stand for me!

There were some major challenges.  First, I wanted to start dry, in which I had no idea before. Second, my previous attempts of growing HC did not go well. Third, it is inside our bedroom so I need to make it aesthetically good, otherwise I might get thrown out of the house along with my little project. Fourth, I did not have any solid plan on the filtration I’d be able to install inside a container this small. I knew I simply can not buy something off the LFS but make something on my own. Fifth, quality commercial substrates like ADA AquaSoil are not available in my country and I needed to come up with a good soil recipe. Sixth, I needed good looking stone pieces suitable for Iwagumi layout.

I bought a 5 gallons bowl from a local store. Also picked up a wall mounting light fixture which can hold a 15W CFL (6500K Phillips) from Nababpur. I had to use a small piece of wood in order to mount it to wall. A local fish-keeping friend of mine helped me with the stones. And my wife bought me a rose wood textured stand from Panthopath.

I mixed garden soil and river mud 3:1, then mixed some earthworm compost 5:1 to the total volume. Later I mixed siphoned water off my tank (with fish waste and poops) with the soil and let it dry a little bit until it became like a dough. I picked some sylhet sand from my other tank and put a 1cm layer in the bowl. Then I added a 2cm layer of the soil. I added the stones on top of the soil layer and played a bit with the formation. At this point I planted a few stems of HC borrowed from a fellow hobbyist inside the bowl, covered the top using a plastic wrap and put it under light. The lighting hours were irregular, from as low as 6 hours to 16 hours a day.

Iwagumi Bowl

Day 01

A few days later, a shipment of plants came to a LFS and I got a pot of HC. I separated and planted each stem individually. I kept misting the plants once a day with fertilizer mixed water.

Iwagumi Bowl

Day 08

After 7 days, I got slight hint of BGA (Blue Green Algae/Cyanobacteria).

Iwagumi Bowl

Day 15

I immediately stopped the fertilizer, switched to plain water, soaked the extra water off the soil using a sponge and cut down on the misting sessions but it did not help a bit, the BGA started to spread rapidly. I tried to cover the BGA by sprinkling a layer of dry sand over the soil in hope to choke it but did not help either.

Iwagumi Bowl

Day 20

From my previous experience I knew it is a bad sign and I did not have any option other than putting medicines. But, previously I dosed the medicine in the water column, so how in the world do I dose Erythromycin in a dry setup? i seriously started to consider flooding the tank and dosing medicine but later I took the simplest option of adding it to the spray bottle. I sprayed two times a day with Erythromycin mixed water. The BGA turned black after three days but I continued to dose for 7 days.

Now I did not have any BGA left but the plants were in bad shape. They simply would not grow and it took them at least three weeks to start growing new leaves. After two months, I had a good enough carpet of HC. Oh, I added some Dwarf Hairgrass too!

Iwagumi Bowl

After two months

I used an airline tube to slowly fill the tank.

Iwagumi Bowl

Filling the tank

I added DIY CO2 (Yeast + Sugar) almost immediately and also added a small 200LH power-head so that the CO2 reaches evenly across the container. I could see good pearling for the next few days. I still need to come up with an idea for filtration and need to decide on what too keep. Currently I have a Nerite snail ruling the bowl!

Iwagumi Bowl

DIY CO2 with DIY Diffuser

Next Week Update:
Its been 7 days since I flooded the bowl and its going steady. I have not noticed any kind of melting, blackening of leaves yet. I have DIY CO2 on 24/7 and a small water-pump for circulation. I have added a DIY filter using a half-cut beverage bottle with holes drilled at the bottom, some synthetic cotton and a small powerhead. The total height of the filter is 4 inch and the diameter is 2 inch. I have used fishing thread to hang the filter from top. The water enters from below, through the synthetic cotton and then pumps back to the bowl by the powerhead. I had two failed prototypes before this design worked. Its been 3 days and the filter is running stable.
I had to change the filtration system. Please read below the update from 24/09/2013.

Iwagumi Bowl

DIY Filtration

Oh I have also added a young pair of my own bred platy in the tank. I will cycle the tank for 3 more weeks and if everything looks okay, I will be adding some shrimps to it.

Iwagumi Bowl7 days after flooding

Update [19/09/2013]:
Facing brown algae (diatom) problem. Reduced the lighting hours from 10 hours to 6 hours. The Nerite snail is too big to clean the brown algae off HC leaves, but it did a nice job cleaning the glass walls. Deployed an Otocinclus today, lets see if this can keep the problem under limit. If I see it cleaning the brown algae, I will put a few more. My only concern is that, since the cycle is not complete, the Otocinclus might have a hard time surviving there. If I see it struggling, I will take it off.

The brown algae appears in new tanks because of the imbalance. As the tank matures, these get over-powered by the plants or other types of green algae. Its been slightly more than a week since I have introduced the filtration system. I am hoping as soon as the bacteria colony establish themselves and the cycle is complete, the tank should recover.

Update [22/09/2013]:
Added 3 pairs of Yellow shrimps (Neocaridina heterpoda var. Yellow) along with the Otos. Removed the pair of Platy.

Update [24/09/2013]:
Spotted severe problem with the filtration. The enclosure was transparent but the bacteria like to grow in the dark. This also explains the instability of the tank since the previous filter actually did nothing but mechanical filtration. Switched to mini spray bar power filter. Installed it with the help of an acrylic piece placed vertically. Cleaned the bowl, did a 50% water change and replaced the filter media with one from my existing tank. Hope this sorts the filtration problem once and for all.
Aaaand spotted a berried shrimp! Yay!!

Iwagumi Bowl

Berried Yellow Shrimp

Update [26/09/2013]:
Facing cloudy water problem. It might be due to the nitrogen cycle being incomplete, another possibility is its just road-side dust. We live beside the main road and our room gets tons of dust everyday.

Update [30/09/2013]:
I experimented by keeping a lid on top of the bowl during the off-light hours and guess what! No more cloudy waters! Also the carpet seems to have covered the bottom of the tank. The submerged growth is at-least twice faster compared to emerged growth. The bowl is stable and running without CO2 for more than two weeks. There has been no sign of algae, brown algae seems of have disappeared as well. I am maintaining a lighting period of 6-6.5 hours daily and 50% water change every 3/4 days.

Iwagumi Bowl

High light promotes compact growth of HC

Iwagumi Bowl

The growth of DHG is out of control

Update [06/10/2013]:
The bowl is stable with no major disaster or algae problem. The rocks are showing slight green tint as a result of maturity. I can rub them off but decided to keep them for now. I have added 6 Galaxy Rasboras. As soon as they settle in the tank I’ll post a picture of them. The filtration system is now working flawlessly with no detectable toxins. The only problem I have is a thin oil layer keeps forming on top of the bowl. I hope this is from the lubricant of the new filter, but if not I’ll have to add in a skimmer of some type. Lighting hours remains at ~7 hours a day with 30% weekly water change.

Update [27/10/2013]:
The tank is stable. Plants growth is steady. No algae issue other than a few strands of Hair Algae which is removed manually while cleaning. The Shrimps and the Rasboras are doing fine.

Iwagumi bowl

Fisheye view

Iwagumi bowl

Shoal of Galaxy Rasboras

With these updates, I am done with this article. Unless there are any major changes, this article is complete.
Thanks for your time.

First post!

Ahh! Finally I have the time to setup my own blog site! I always had big plans for this, probably too big! That’s why all those big ideas never turned to reality. This time I’ve decided to go as simple as possible and will be trying to gradually improve the site. I hope this new strategy works!