Frequent Asked Questions | D-D The Aquarium Solution

to whom it may concerned
today i purchased the said product inn the subject from our local shop on recommendationn
so i mixed 25 litres up using the correct procedure.RO WATER TESTED before mixing using an refactometre setting was zero as it should be for ro water.slowly added your salt mix in a clean container (clean out using ro water).got the salinity up 1.025 and left it mixing for 5 hrs with an wave maker placed in the container for better mixing and heater placed in as well this is how i mix my salts, i then shive the mix into a clean 25 litre container (using a very fine filter seive) .upon testing the mix for nitrates we have noticed their is slight presence of the said nitrates in the mix.considering the RO WATER was free of no3 and container had been fully cleaned out it seems that the nitrates as come from your product mentioned.we have found out that you's had this problem before in the past (mentioned on the internet forums). can you explained why it is now happening again . am more than happy to send pictures of this if need be. the test kit used was salifert nitrate no3 profi test and the batch is in date 11-2018.the result was showing the low range scale of the colour chart between 0.2-0.5mg/L.

the tub was a 6.6kg with lot number :511239/274 and the numbers under is 1707160101

the nitrate is only minor but does not help, but it clearly states on your product free from nitrates and phosphates.

as it stand this is False advertising and misleading of an product information on your behalf

i await for your replie



I am thinking of buying the SC1660 protein skimmer and wanted to check a couple of 
points first. I will use the protein skimmer with a Neptune controller which turns 
off the power for feeding. Will the protein skimmer be OK with this and return to the 
power setting prior to it being turned of? Also I have not been happy with 
the Vertex protein skimmer I have because of the noise and lack of any customer 
support. Should the DC pump be quieter than the AC one in the VerXex and can 
I get spare parts? I have just purchased a new impeller for the VerXex which 
snapped within 24 hours. I am told that this part has no warrantee so all I 
can do is buy another one. Is this your policy also?


I have been on your faqs regarding flowrate but cant get my head around it!
Can you work out the required flowrate for me please I have the 39w uv in a 
800lt tank and need it to kill whitespot. Thanks

I have just purchased a DD refractometer as I was having a lot of issues with my RS refractometer.

The DD refractometer is as stable as the forums said so I am certainly pleased with my purchase.

However I would prefer to calibrate it with calibration fluid (35 ppt, refractive index 1.3394 @ 25 degC) the product is :

To what value should I calibrate the refractometer as the refractometer is at 20 degC but the fluid is at 25degC?

For info when I calibrated the refractometer using the fluid , the RO water sample supplied with the unit then gives a slightly above zero reading (reading ≈ 0.002)

Therefore I would truly appreciate some insight on this.

thanks in advance.

I am wondering if you may be able to help, currently my systemn is being maintained to a quality standard of approx 90%,  its my nitrates that are letting me down,  i currently use rowaphos in the D-D reactor, which is working fab, however i need to get my nitrates down,  so my question to you is,  can i use a liquid carbon source along side your rowaphos, will it cause an issues or non functioning of the rowaphos

Kind Regards


I have a small water cooler dc300, it seams to have lost it effectiveness, can these coolers be recharged with coolant,  thanks b

hi  Can I use the AI SOL for a tropical freshwater aquarium and if so what light level settings would be required for a planted and fish set up.


Hi there,

Does the D-D Slimline designer bracket attach to a braced tank, or is it 
designed for braceless?

If so, Is there a particular distance from the rim of the tank to the braces 
that needs to be met?

Many thanks,

Hi Stuart,


I hope you don't mind me asking another question.


I am really torn between 2 x 52s and 3 x 26s.  With the price of th eextra bracket, there isn't much difference in price.  In my mind I thought that 2 x 52HDs would give me 8 clusters of LEDs, whereas the 3 x 26HDs only 6.  Make sense?  Then I reread your email where you advised me that 3 x 26HDs might be the best way and you stated that "3 x Hydra 26 has about the same power as 2 x Hydra 52".  Am I missing something?  Do the 26HDs have more power per cluster?


Really grateful for your advice here - it's a big investment for me!



Hi can you tell me if Rowaphos will remove red sea 
nitrate/phosphate reducer thanks.

Hi I have just bought 2 of your excellent lights the Hydra 52 
HDs but I'm having trouble setting setting the light duration I want the 
lights to come on at 8.00am I have done that bit then ramp up for 10.00am 
then from 10.00am till 6.00pm constant then I want them to go off at 9.00pm 
but there not going off at 9.00pm what am I doing wrong I 
just don't understand.

Hi I've recently bought the nitrate filter along with a 32ml dd peri pump and 
1ml peri pump , my tank is 600 litres , I'm struggling to slow to flow down 
to a drip every couple of seconds without the airline tube blowing off to 
Peru pump to the tap on the filter , is there something I'm doing wrong ? 
Just that every time I try adjust the flow of wAter coming in the tube just 
comes off
Thanks in advanced tom

We have just bought a chiller though Maidenhead Aquatics in Guildford.  It was set at maximum of 26 C but last night it went up to 26.4 C.  I checked the settings - by holding SET for 3 seconds and it was indeed still set to a maximum of 26.  The tank holds about 450 litres so I would have thought the DC-750 would be powerful enough to keep it at 26 C. 

Any ideas?

I know you are an expert on Hydra’s but if you are not familiar with chillers, do you have an equivalent to you for the DC Series?

Hi, I have a dc750 chiller and I have noticed a few problems 
with it recently. It seems to take a long time to chill (so probably needs 
gassing) and it has now started to get "stuck" on 26.9 degrees. It was bought 
5/6 years ago online and I have been unable to retrieve the information 
regarding its purchase. Do you provide servicing of chillers? If not what do 
you recommend I do to overcome the issues I'm experiencing?

Could you please explain the reason for the 8 stage settings on the DC PUMP, and what settings on these for the sump return pump set at 6000 ltrs per hour
Kind Regards