Only 3 of 9 sprouted - WHY?

I got 10 Joey Weed Blue Widow seeds.
I put them in General Hydroponics Rapid Rooter Plugs.
I used my Ph calibration screw driver to create new holes and put the seeds JUST below the surface.
I put them in a tray with about 3/4" of distilled water with Hyroton® clay pellets between them to help hold them up.
I have a transparant plastic dome covering them.
I put them under 160 watts of 4' Flourescents about 8" above them 18/6.
Temperature was consistently between 70ºF and 85ºF.

The Ph continually rizes. I keep putting lemon juice in the water to pull the Ph down. I've dropped it as low as 4.5. In 5 hours it's back up to 6 +.
This has been going on for 6 days now. WHY?

Only 3 of 9 seeds sprouted. They all cracked. One grew a root about 3/4" long but the stem never came out of the seed.
All of them cracked but only 3 sprouted.
So far, the 3 look good (6 days).

WHAT DID I DO WRONG??

Patience...I planted ten seeds in similar setup (rockwool cubes only real difference, and stable ph) and I had 3 sprout in 48 hours, in 6 days had 7 and after 11 days had all 10. So, each seed can take it's time. Make sure they are moist, not wet, so they don't rot. But leave them be. If that doesn't work, you can pull them out and if they are still viable, you can scuff them. There is many many germination tricks...but this works for me, and I so far have had an 80& success rate.

Hmm, thanks. I'll keep watching them.
What does 'scuff them' mean?

Well, still nothing out of those seeds. They cracked but nothing more. I musta done something wrong.
Also, how can I stabalize the Ph? It's all over the place.
Lemon Juice brings it back down but not for long . . .

me personally germanate in compost they normally shoot through in three days and if done wright normally get all up and avoid touch kill which can happen moving sprouted seeds if you want to practice this method go to a fishing tackle shop and buy some hemp seeds and practice with them you will get a bag full of uncooked hemp seed 4 about £1.50 dont set the seed too deep about 2 or three mm keep quite moist dont let top dry as the seed is only shallow