Can play sand be used?

you can use it but it is a mess from personal experience it takes forever to calm down when you first use it. I rinsed mine several times in a five gallon bucket then put it in my 55. the water stayed cloudy for at least a month and it was a real hassle with water changes. Ive heard ppl use pool sand maybe you might wanna look at that option. you can probably search sand or play sand and get a lot of threads about this topic. Most of the opinions that I have read are mixed. Mine just happens to be against. If you do go the play sand route just make sure to put a plate on top of the sand where your gonna pour water in or it gets really bad.
 
It is perfectly fine to use, you just have to rinse the crap out of it, and I mean rinse, rinse, rinse and then rinse some more. I have it is several of my tanks. Pool filter sand is fine as well, the only real difference is the color of the two in my opinion.
 
Pool Filter Sand-PFS, is easy to find and in-expensive. I picked up a 50# bag at my local farm store for less than $6. I rinsed it in a bucket for a bit (put in bucket, add water, swish with hands, dump water..repeat) just for a bit then put in tank. It settled in less than an hour and was clear from then on out. I have enough left over to do a few more smaller tanks as well.

Easy to use, is inert and won't mess with your water chemistry, easy to rinse, and cost very little. To me it's a no brainer.
 
With African cichlids, if your tap water is already hard and alkaline, you'd do just fine with ordinary pool filter sand (I have it in all my FW tanks and love it). I have never used play sand so I cannot offer an opinion on it. The Aragonite sand posted would be a good choice if your tap water is soft. Many people with African cichlids often add a buffer and GH booster to their water to make it better suited for these fish anyway, so the aragonite sand would surely help with that. Besides, if you ever wanted to go saltwater at least you'd have the recommended sand already.
 
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